It may be worth mentioning that the 2024 version of the "Alert" feat allows you to swap positions in the initiative order with a willing ally right after the initiative roll. It's a lot more limited than the old Delay action, but it can be handy in situations where you've rolled high on initiative but don't know what you want to do yet.
It may be worth mentioning that the 2024 version of the "Alert" feat allows you to swap positions in the initiative order with a willing ally right after the initiative roll. It's a lot more limited than the old Delay action, but it can be handy in situations where you've rolled high on initiative but don't know what you want to do yet.
The best house rule I've been able to come up with for making surprise function coherently without the overwhelming impact of a surprise round is
Surprise: in a potential surprise situation, the characters attempting surprise roll stealth instead of initiative, and the potentially surprised targets have their initiative limited to their passive perception. Note that, if one character decides to launch an attack without informing the rest of the party, they count as potentially surprised. This provides a simple explanation for the ambushers losing initiative in a surprise situation: you were clumsy enough that your victims spotted you.
5E24 surprise and Initiative rules between the Player's Handbook and Dungeon Master Guide offers me enought guidelines to come up with various options;
Surprise. If a combatant is surprised by combat starting, that combatant has Disadvantage on their Initiative roll. For example, if an ambusher starts combat while hidden from a foe who is unaware that combat is starting, that foe is surprised.
Surprise. If you’re Invisible when you roll Initiative, you have Advantage on the roll.
Rolling Initiative. In any situation where a character’s actions initiate combat, you can give the acting character Advantage on their Initiative roll.
Advantage and Disadvantage. If a creature has Advantage on Initiative rolls, increase its Initiative score by 5. If it has Disadvantage on those rolls, decrease that score by 5.
Initiative Scores for Characters. You can get to the action of combat more quickly by using Initiative scores instead of rolling. You might decide to use Initiative scores just for characters, just for monsters, or for both. A character’s Initiative score is typically 10 plus all modifiers to the character’s Initiative roll (including their Dexterity modifier and any special modifiers).
Ties. If a tie occurs, the DM decides the order among tied monsters, and the players decide the order among tied characters. The DM decides the order if the tie is between a monster and a player character.
5E24 surprise and Initiative rules between the Player's Handbook and Dungeon Master Guide offers me enought guidelines to come up with various options;
Surprise. If a combatant is surprised by combat starting, that combatant has Disadvantage on their Initiative roll. For example, if an ambusher starts combat while hidden from a foe who is unaware that combat is starting, that foe is surprised.
Surprise. If you’re Invisible when you roll Initiative, you have Advantage on the roll.
Rolling Initiative. In any situation where a character’s actions initiate combat, you can give the acting character Advantage on their Initiative roll.
Advantage and Disadvantage. If a creature has Advantage on Initiative rolls, increase its Initiative score by 5. If it has Disadvantage on those rolls, decrease that score by 5.
Initiative Scores for Characters. You can get to the action of combat more quickly by using Initiative scores instead of rolling. You might decide to use Initiative scores just for characters, just for monsters, or for both. A character’s Initiative score is typically 10 plus all modifiers to the character’s Initiative roll (including their Dexterity modifier and any special modifiers).
Ties. If a tie occurs, the DM decides the order among tied monsters, and the players decide the order among tied characters. The DM decides the order if the tie is between a monster and a player character.
Absolutely none of what you posted in any way addresses the issues raised in the OP or in the discussion we have been having. Did you not read anything but the title before posting? We know what the rules say. I was asking what the expected implementation of those rules looks like and we were discussing wither that expected implementation is good/reasonable.
The best house rule I've been able to come up with for making surprise function coherently without the overwhelming impact of a surprise round is
Surprise: in a potential surprise situation, the characters attempting surprise roll stealth instead of initiative, and the potentially surprised targets have their initiative limited to their passive perception. Note that, if one character decides to launch an attack without informing the rest of the party, they count as potentially surprised. This provides a simple explanation for the ambushers losing initiative in a surprise situation: you were clumsy enough that your victims spotted you.
I get where you are trying to go with that but it seems unnecessarily complex.
I think it makes more sense to roll the stealth check and use passive perception first. Just as you would for anything else they may or may not notice. Then if they do not spot the ambush allow the ambusher and any allies who are aware that combat is about to start to go automatically at the top of initiative. Then everyone else rolls initiative normally.
That way you guarantee the person who breaks their successful hiding and starts the attack always goes first, and the party doesn't always go in the same order. Plus it is the most similar to ordinary rolling of initiative and ordinary use of passive perception so it is easier to remember and handle.
It also works perfectly well if one character hauls off and starts combat without others being aware they are intending to do so. That character goes first and everyone else rolls because they are all surprised.
Nobody ever gets to super humanly know combat is happening, nor do they ever roll super well but end up effectively going last.
It may be worth mentioning that the 2024 version of the "Alert" feat allows you to swap positions in the initiative order with a willing ally right after the initiative roll. It's a lot more limited than the old Delay action, but it can be handy in situations where you've rolled high on initiative but don't know what you want to do yet.
And to really get the most from the feat, combine it with Find Familiar. Since your familiar rolls its own initiative, you always have two results to choose from without putting a party member in an awkward position.
5E24 surprise and Initiative rules between the Player's Handbook and Dungeon Master Guide offers me enought guidelines to come up with various options;
Surprise. If a combatant is surprised by combat starting, that combatant has Disadvantage on their Initiative roll. For example, if an ambusher starts combat while hidden from a foe who is unaware that combat is starting, that foe is surprised.
Surprise. If you’re Invisible when you roll Initiative, you have Advantage on the roll.
Rolling Initiative. In any situation where a character’s actions initiate combat, you can give the acting character Advantage on their Initiative roll.
Advantage and Disadvantage. If a creature has Advantage on Initiative rolls, increase its Initiative score by 5. If it has Disadvantage on those rolls, decrease that score by 5.
Initiative Scores for Characters. You can get to the action of combat more quickly by using Initiative scores instead of rolling. You might decide to use Initiative scores just for characters, just for monsters, or for both. A character’s Initiative score is typically 10 plus all modifiers to the character’s Initiative roll (including their Dexterity modifier and any special modifiers).
Ties. If a tie occurs, the DM decides the order among tied monsters, and the players decide the order among tied characters. The DM decides the order if the tie is between a monster and a player character.
Absolutely none of what you posted in any way addresses the issues raised in the OP or in the discussion we have been having. Did you not read anything but the title before posting? We know what the rules say. I was asking what the expected implementation of those rules looks like and we were discussing wither that expected implementation is good/reasonable.
Are you asking this seriously or just to come off as rude? I addressed it in post #18 like 3 days ago which you replied if you remember. This post is in response to the one above with rules put in context and which answer OP questions such as How do you handle surprise in your games?
I think the high initiative players would get a sense somthing dangerous is happening, and have a chance to cast defensive spells, seek cover, make an active perception check, push a low HP character out of room, or otherwise make a last second effort to defend from an unknown threat.
In our group, we too see the same problem as described in the OP.
We will apply this house rule that should both be true to the intent of the 2024 change and not produce logic issues:
"If Combat is triggered by an Action or Bonus Action, that cannot be anticipated (e.g., because a creature causing the effect has the Invisible condition), for the first round of combat, the creature taking this action takes the first turn. After the first round, turns are taken in order of Initiative."
I think the resolution here is that the rules say that the DM decides when initiative is rolled. So what I've gone to is as follows:
--(1) In a scenario where an action that starts combat is readily apparent before any attacks are made, roll initiative right away, as per the rules. ie, the fighter starts to draw his sword in the middle of negotiations - disadvantage to everyone not expecting it. This is what the 2024 rules actually cover.
--(2) In a scenario where the action that might start combat is ambiguous, determine for the NPCs or ask the players if they wish to react as if the action is hostile. ie, the sorceror starts visibly casting a spell. Note: this cannot always be hostile, as Charm Person applies a penalty if you're in combat, so it must be able to be cast without starting combat. If they do react as if it's hostile, roll initiative, determine advantage based on whether it was actually hostile, or it wasn't (and the side reacting is the one actually initiating combat and the first side gets disadvantage). If they don't react and it was hostile, then see scenario 3 below. (I suppose there's also the situation where one side reacts to the ambiguous action by the other with an ambiguous action of their own, which leads to determining for the other side as well whether they think that is hostile. The DM can figure it out).
--(3) In a scenario where there's no way the other side could be aware combat was about to start (or one side ignored the possibility combat was starting in #2), the first attack or offensive spell happens, then you roll initiative. (The result of the spell or attack is what starts combat, not making the attack or casting the spell). So bandits successfully hidden attacking from ambush (first an attack happens, then roll initiative). Note the first attack is one person, not the entire side. This also covers the sorceror casting a hostile subtle spell (where the first indication combat has begun is the spell going off).
All fully RAW, as the DM decides when combat has started and initiative is to be rolled. When the thing that starts the combat is the result of an attack or offensive spell, combat starts afterwards. That's the only sane decision for the DM to make.
No metagaming. No weird 'why did combat start?' Combat starts when everyone knows they're in combat, and not before.
And importantly, no Schroedinger's combat. ie, no situation where the surprised side wins initiative, so the surprising party decides not to take the action that triggered the initiative rolls in the first place (because they're not committed to taking that action). It's a narrative nightmare, especially in the case where the surprised side still isn't aware of anything that would actually tell them combat is about to start. So everyone dodges or runs for cover or casts spells and... nothing happens. So we leave initiative order and the surprising party decides to declare they're taking an action which would start combat again. Repeat until they finally get to act first. If you interpret the rules to say you roll initiative before the other side has any reason to know they're in combat, you get really stupid things.
The weirdest thing about 5.x surprise rules is the examples they use don't even represent the normal 'surprise' conditions. IIRC, it's something like 'a sorceror starts casting a spell because he's decided the NPC is a shapechanger'. On the one hand, a sorceror casting a spell is not necessarily a hostile action (and can't be, as there are spells clearly intended to be cast not in combat, like Charm Person), so just the act of casting a spell shouldn't be enough to roll initiative. On the other hand, that's an action visible to the 'enemy', so they may be surprised but not totally unaware. However, the normal surprise situation in D+D is attacking from ambush against an enemy who is entirely unaware of you. Surprise initiative should not be a second chance to accomplish what your perception already failed to do.
But really, 3.5 had the best surprise rules. We should just go back to using those.
On the one hand, a sorceror casting a spell is not necessarily a hostile action (and can't be, as there are spells clearly intended to be cast not in combat, like Charm Person), so just the act of casting a spell shouldn't be enough to roll initiative.
Well, that depends. Casting a spell starts combat if the characters you are interacting with would interpret casting a spell as initiating combat. There aren't any particular rules on that, but I would say that typically a hostile creature will consider casting an unknown spell as starting combat, a friendly creature will not, and an indifferent creature may or may not depending on the situation.
Keep in mind that the example of the Sorcerer casting a spell during negotiation has nothing to do with surprise. That example illustrates that the DM may decide to give the initiating creature advantage depending on the situation.
Surprise has to do with not knowing that combat is starting because you are unable to perceive the beginning of combat and this results in disadvantage for some creatures, not advantage.
If a surprised creature wins initiative anyway then they act first as normal. They presumably know that they are in imminent danger for some reason that would have to be narrated but they don't know exactly where the threat is coming from. Since they act first they can try to guess where the threat is coming from with a "guess the square" attack or an AoE spell or whatever if they so choose. Or they might Ready an attack. Or move. Or, the character might attempt any of the things mentioned in this earlier post, among other things:
I think the high initiative players would get a sense somthing dangerous is happening, and have a chance to cast defensive spells, seek cover, make an active perception check, push a low HP character out of room, or otherwise make a last second effort to defend from an unknown threat.
All fully RAW, as the DM decides when combat has started and initiative is to be rolled. When the thing that starts the combat is the result of an attack or offensive spell, combat starts afterwards. That's the only sane decision for the DM to make.
No metagaming. No weird 'why did combat start?' Combat starts when everyone knows they're in combat, and not before.
And importantly, no Schroedinger's combat. ie, no situation where the surprised side wins initiative, so the surprising party decides not to take the action that triggered the initiative rolls in the first place (because they're not committed to taking that action). It's a narrative nightmare, especially in the case where the surprised side still isn't aware of anything that would actually tell them combat is about to start. So everyone dodges or runs for cover or casts spells and... nothing happens. So we leave initiative order and the surprising party decides to declare they're taking an action which would start combat again. Repeat until they finally get to act first. If you interpret the rules to say you roll initiative before the other side has any reason to know they're in combat, you get really stupid things.
The weirdest thing about 5.x surprise rules is the examples they use don't even represent the normal 'surprise' conditions. IIRC, it's something like 'a sorceror starts casting a spell because he's decided the NPC is a shapechanger'. On the one hand, a sorceror casting a spell is not necessarily a hostile action (and can't be, as there are spells clearly intended to be cast not in combat, like Charm Person), so just the act of casting a spell shouldn't be enough to roll initiative. On the other hand, that's an action visible to the 'enemy', so they may be surprised but not totally unaware. However, the normal surprise situation in D+D is attacking from ambush against an enemy who is entirely unaware of you. Surprise initiative should not be a second chance to accomplish what your perception already failed to do.
Rolling initiative is an action outside the narrative, so that sequencing can be managed in a situation where sequencing may matter.
Charm Person has no inherent penalty in combat. It has a penalty if you are fighting the target. If you are not yet fighting the target, there is no penalty just because you've moved to combat time.
Your insistence that everybody needs to know they're in combat in order to use the combat rules is the source of most of your problems with the initiative/surprise rules.
Do they sometimes create issues? Yes. But if players are capable of separating player and character knowledge, most issues are going to be minor. (I do not believe it is possible for a system to not create issues in all possible scenarios.)
If a surprised creature wins initiative anyway then they act first as normal. They presumably know that they are in imminent danger for some reason that would have to be narrated but they don't know exactly where the threat is coming from. Since they act first they can try to guess where the threat is coming from with a "guess the square" attack or an AoE spell or whatever if they so choose. Or they might Ready an attack. Or move. Or, the character might attempt any of the things mentioned in this earlier post, among other things:
This is total nonsense to me, and I would never allow someone to act as if there was a threat if they don't perceive a threat. Initiative is not a do-over when your perception fails. Neither creatures nor characters have 'spidey sense' (unless a rule specifically gives it to them).
The rules are quite specific that the DM decides when combat starts and initiative is rolled. And the sensible point to start is when both sides are aware they're in combat. And nothing in the rules stops the DM from deciding that combat begins then.
And this is narratively what makes sense. The guy in front taking an arrow to the knee causes everyone to scramble for cover. Plenty of movie scenes work like that. The only time, narratively, someone gets suspicious before the first shot is when they perceive something that makes them suspicious. That's a perception check, not rolling well on initiative. So no, i disagree, rolling high on initiative is not permission to start suddenly casting a spell or taking defensive action - being unaware means being unaware.
And your version breaks down the moment the initiating event is completely imperceptible. Let's say a spellcaster casts Dominate Person without components (subtle spell, enchantment adept, etc...). Do you roll initiative before he casts? If the target passes his save, the target doesn't even know it was the target of a spell. If the target fails his save, there's no indication of hostile action, and thus no combat. So there's no argument here that combat even starts. But if the spellcaster instead imperceptibly casts fireball, then how could combat start because of that casting? There's no perceptible difference between fireball and dominate person until the fireball explodes. This has to be adjudicable without knowing what spell is being cast, because in-world the "enemies" don't know what spell is being cast (or even that a spell is being cast).
What you think the rules require is a narrative trainwreck and more corrosive to causality than a time travel plot device. Fortunately, the rules don't require any such thing. The DM is empowered to wait to roll initiative until combat has actually started.
All fully RAW, as the DM decides when combat has started and initiative is to be rolled. When the thing that starts the combat is the result of an attack or offensive spell, combat starts afterwards. That's the only sane decision for the DM to make.
No metagaming. No weird 'why did combat start?' Combat starts when everyone knows they're in combat, and not before.
And importantly, no Schroedinger's combat. ie, no situation where the surprised side wins initiative, so the surprising party decides not to take the action that triggered the initiative rolls in the first place (because they're not committed to taking that action). It's a narrative nightmare, especially in the case where the surprised side still isn't aware of anything that would actually tell them combat is about to start. So everyone dodges or runs for cover or casts spells and... nothing happens. So we leave initiative order and the surprising party decides to declare they're taking an action which would start combat again. Repeat until they finally get to act first. If you interpret the rules to say you roll initiative before the other side has any reason to know they're in combat, you get really stupid things.
The weirdest thing about 5.x surprise rules is the examples they use don't even represent the normal 'surprise' conditions. IIRC, it's something like 'a sorceror starts casting a spell because he's decided the NPC is a shapechanger'. On the one hand, a sorceror casting a spell is not necessarily a hostile action (and can't be, as there are spells clearly intended to be cast not in combat, like Charm Person), so just the act of casting a spell shouldn't be enough to roll initiative. On the other hand, that's an action visible to the 'enemy', so they may be surprised but not totally unaware. However, the normal surprise situation in D+D is attacking from ambush against an enemy who is entirely unaware of you. Surprise initiative should not be a second chance to accomplish what your perception already failed to do.
Rolling initiative is an action outside the narrative, so that sequencing can be managed in a situation where sequencing may matter.
Charm Person has no inherent penalty in combat. It has a penalty if you are fighting the target. If you are not yet fighting the target, there is no penalty just because you've moved to combat time.
Your insistence that everybody needs to know they're in combat in order to use the combat rules is the source of most of your problems with the initiative/surprise rules.
Do they sometimes create issues? Yes. But if players are capable of separating player and character knowledge, most issues are going to be minor. (I do not believe it is possible for a system to not create issues in all possible scenarios.)
My insistence on causality being linear and the narrative making sense is not my problem with the rules, it's a problem with your interpretation of the rules. As I note, the DM decides when combat starts. There is no obligation to call for initiative when you say there is. So my interpretation is fully rules compliant. The rules aren't the problem, your understanding of when you roll initiative is the problem.
I welcome anyone to point out any issues my interpretation creates, because I don't believe there are any.
And I'm sorry, but how would you define 'fighting a creature' that wasn't 'be in combat with that creature'? There's no difference to be drawn there; it's tautological: you're fighting it immediately upon rolling initiative. (I presume here that casting charm person is what 'started the combat', so the target is included in the group that is now classed as 'enemy' by construction, and not just a random bystander.)
(BTW, it's not even metagaming under your interpretation of the rules. Constructing scenarios where the aggressor is unperceived, and can simply neglect to take hostile action if they don't win initiative, is trivial -- and what ambusher would proceed with an ambush if they thought their victims had become alerted to them, but could withdraw or stay hidden without issue if they don't proceed? It's the sensible in-character decision to wait for a better opportunity.)
On the one hand, a sorceror casting a spell is not necessarily a hostile action (and can't be, as there are spells clearly intended to be cast not in combat, like Charm Person), so just the act of casting a spell shouldn't be enough to roll initiative.
Well, that depends. Casting a spell starts combat if the characters you are interacting with would interpret casting a spell as initiating combat. There aren't any particular rules on that, but I would say that typically a hostile creature will consider casting an unknown spell as starting combat, a friendly creature will not, and an indifferent creature may or may not depending on the situation.
I think I said something similar in how I'd interpret the rules for when the DM decides initiative is rolled.
Also, if you agree the act of casting a spell shouldn't be enough to roll initiative, then you agree that (if creatures don't perceive the act of casting itself as hostile) it doesn't matter what spell is being cast, and would thus be the results of spellcasting which would potentially start combat after the spell has gone off.
In the odd case that you're surprised by combat starting but acting first in turn order, i don't have an issue explaining it with an intuition or danger sense if you haven't yet perceived an imminent threat.
You can still move, Dodge, use Magic, Ready an action of some sort, Search for concealed creatures, or attempt to Attack one by targeting it's location for example.
My take on this has evolved somewhat over the time I've spent thinking about it. I'm now probably going to use Ready out of combat to deal with situations of surprise beyond DIS on initiative. That is, if you want to actually act before someone and are planning on initiating combat (standard ambush scenario), then they Ready an attack with a appropriate trigger. As long as it isn't a spell, they can simply Ready until the trigger happens, no matter how long it takes.
Now, combat starts, initiative is rolled, and then the first thing to happen is the Readied action (using the creature's Reaction). All initiative flows from there.
I think lowers the power of the "surprise round" sufficiently while still making narrative and mechanical sense.
In the odd case that you're surprised by combat starting but acting first in turn order, i don't have an issue explaining it with an intuition or danger sense if you haven't yet perceived an imminent threat.
You can still Ready an action of some sort, Search for concealed creatures, or attempt to Attack one by targeting it's location.
How can you be 'surprised by combat starting' if combat hasn't even started yet?
In the odd case that you're surprised by combat starting but acting first in turn order, i don't have an issue explaining it with an intuition or danger sense if you haven't yet perceived an imminent threat.
You can still Ready an action of some sort, Search for concealed creatures, or attempt to Attack one by targeting it's location.
How can you be 'surprised by combat starting' if combat hasn't even started yet?
You can be suprised by combat starting at the start of combat when Initiative is rolled when no spell or attack was made yet as the rules explained.
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It may be worth mentioning that the 2024 version of the "Alert" feat allows you to swap positions in the initiative order with a willing ally right after the initiative roll. It's a lot more limited than the old Delay action, but it can be handy in situations where you've rolled high on initiative but don't know what you want to do yet.
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Thanks. That is a good point to be aware of.
The best house rule I've been able to come up with for making surprise function coherently without the overwhelming impact of a surprise round is
5E24 surprise and Initiative rules between the Player's Handbook and Dungeon Master Guide offers me enought guidelines to come up with various options;
Absolutely none of what you posted in any way addresses the issues raised in the OP or in the discussion we have been having. Did you not read anything but the title before posting? We know what the rules say. I was asking what the expected implementation of those rules looks like and we were discussing wither that expected implementation is good/reasonable.
I get where you are trying to go with that but it seems unnecessarily complex.
I think it makes more sense to roll the stealth check and use passive perception first. Just as you would for anything else they may or may not notice.
Then if they do not spot the ambush allow the ambusher and any allies who are aware that combat is about to start to go automatically at the top of initiative. Then everyone else rolls initiative normally.
That way you guarantee the person who breaks their successful hiding and starts the attack always goes first, and the party doesn't always go in the same order. Plus it is the most similar to ordinary rolling of initiative and ordinary use of passive perception so it is easier to remember and handle.
It also works perfectly well if one character hauls off and starts combat without others being aware they are intending to do so. That character goes first and everyone else rolls because they are all surprised.
Nobody ever gets to super humanly know combat is happening, nor do they ever roll super well but end up effectively going last.
And to really get the most from the feat, combine it with Find Familiar. Since your familiar rolls its own initiative, you always have two results to choose from without putting a party member in an awkward position.
Are you asking this seriously or just to come off as rude? I addressed it in post #18 like 3 days ago which you replied if you remember. This post is in response to the one above with rules put in context and which answer OP questions such as How do you handle surprise in your games?
I think the high initiative players would get a sense somthing dangerous is happening, and have a chance to cast defensive spells, seek cover, make an active perception check, push a low HP character out of room, or otherwise make a last second effort to defend from an unknown threat.
In our group, we too see the same problem as described in the OP.
We will apply this house rule that should both be true to the intent of the 2024 change and not produce logic issues:
"If Combat is triggered by an Action or Bonus Action, that cannot be anticipated (e.g., because a creature causing the effect has the Invisible condition), for the first round of combat, the creature taking this action takes the first turn. After the first round, turns are taken in order of Initiative."
I think the resolution here is that the rules say that the DM decides when initiative is rolled. So what I've gone to is as follows:
--(1) In a scenario where an action that starts combat is readily apparent before any attacks are made, roll initiative right away, as per the rules. ie, the fighter starts to draw his sword in the middle of negotiations - disadvantage to everyone not expecting it. This is what the 2024 rules actually cover.
--(2) In a scenario where the action that might start combat is ambiguous, determine for the NPCs or ask the players if they wish to react as if the action is hostile. ie, the sorceror starts visibly casting a spell. Note: this cannot always be hostile, as Charm Person applies a penalty if you're in combat, so it must be able to be cast without starting combat. If they do react as if it's hostile, roll initiative, determine advantage based on whether it was actually hostile, or it wasn't (and the side reacting is the one actually initiating combat and the first side gets disadvantage). If they don't react and it was hostile, then see scenario 3 below. (I suppose there's also the situation where one side reacts to the ambiguous action by the other with an ambiguous action of their own, which leads to determining for the other side as well whether they think that is hostile. The DM can figure it out).
--(3) In a scenario where there's no way the other side could be aware combat was about to start (or one side ignored the possibility combat was starting in #2), the first attack or offensive spell happens, then you roll initiative. (The result of the spell or attack is what starts combat, not making the attack or casting the spell). So bandits successfully hidden attacking from ambush (first an attack happens, then roll initiative). Note the first attack is one person, not the entire side. This also covers the sorceror casting a hostile subtle spell (where the first indication combat has begun is the spell going off).
All fully RAW, as the DM decides when combat has started and initiative is to be rolled. When the thing that starts the combat is the result of an attack or offensive spell, combat starts afterwards. That's the only sane decision for the DM to make.
No metagaming. No weird 'why did combat start?' Combat starts when everyone knows they're in combat, and not before.
And importantly, no Schroedinger's combat. ie, no situation where the surprised side wins initiative, so the surprising party decides not to take the action that triggered the initiative rolls in the first place (because they're not committed to taking that action). It's a narrative nightmare, especially in the case where the surprised side still isn't aware of anything that would actually tell them combat is about to start. So everyone dodges or runs for cover or casts spells and... nothing happens. So we leave initiative order and the surprising party decides to declare they're taking an action which would start combat again. Repeat until they finally get to act first. If you interpret the rules to say you roll initiative before the other side has any reason to know they're in combat, you get really stupid things.
The weirdest thing about 5.x surprise rules is the examples they use don't even represent the normal 'surprise' conditions. IIRC, it's something like 'a sorceror starts casting a spell because he's decided the NPC is a shapechanger'. On the one hand, a sorceror casting a spell is not necessarily a hostile action (and can't be, as there are spells clearly intended to be cast not in combat, like Charm Person), so just the act of casting a spell shouldn't be enough to roll initiative. On the other hand, that's an action visible to the 'enemy', so they may be surprised but not totally unaware. However, the normal surprise situation in D+D is attacking from ambush against an enemy who is entirely unaware of you. Surprise initiative should not be a second chance to accomplish what your perception already failed to do.
But really, 3.5 had the best surprise rules. We should just go back to using those.
Well, that depends. Casting a spell starts combat if the characters you are interacting with would interpret casting a spell as initiating combat. There aren't any particular rules on that, but I would say that typically a hostile creature will consider casting an unknown spell as starting combat, a friendly creature will not, and an indifferent creature may or may not depending on the situation.
Keep in mind that the example of the Sorcerer casting a spell during negotiation has nothing to do with surprise. That example illustrates that the DM may decide to give the initiating creature advantage depending on the situation.
Surprise has to do with not knowing that combat is starting because you are unable to perceive the beginning of combat and this results in disadvantage for some creatures, not advantage.
If a surprised creature wins initiative anyway then they act first as normal. They presumably know that they are in imminent danger for some reason that would have to be narrated but they don't know exactly where the threat is coming from. Since they act first they can try to guess where the threat is coming from with a "guess the square" attack or an AoE spell or whatever if they so choose. Or they might Ready an attack. Or move. Or, the character might attempt any of the things mentioned in this earlier post, among other things:
Surprising a creature may result Advantage to Initiative if you're Invisible, which is most often the case when hidden for example.
Rolling initiative is an action outside the narrative, so that sequencing can be managed in a situation where sequencing may matter.
Charm Person has no inherent penalty in combat. It has a penalty if you are fighting the target. If you are not yet fighting the target, there is no penalty just because you've moved to combat time.
Your insistence that everybody needs to know they're in combat in order to use the combat rules is the source of most of your problems with the initiative/surprise rules.
Do they sometimes create issues? Yes. But if players are capable of separating player and character knowledge, most issues are going to be minor. (I do not believe it is possible for a system to not create issues in all possible scenarios.)
This is total nonsense to me, and I would never allow someone to act as if there was a threat if they don't perceive a threat. Initiative is not a do-over when your perception fails. Neither creatures nor characters have 'spidey sense' (unless a rule specifically gives it to them).
The rules are quite specific that the DM decides when combat starts and initiative is rolled. And the sensible point to start is when both sides are aware they're in combat. And nothing in the rules stops the DM from deciding that combat begins then.
And this is narratively what makes sense. The guy in front taking an arrow to the knee causes everyone to scramble for cover. Plenty of movie scenes work like that. The only time, narratively, someone gets suspicious before the first shot is when they perceive something that makes them suspicious. That's a perception check, not rolling well on initiative. So no, i disagree, rolling high on initiative is not permission to start suddenly casting a spell or taking defensive action - being unaware means being unaware.
And your version breaks down the moment the initiating event is completely imperceptible. Let's say a spellcaster casts Dominate Person without components (subtle spell, enchantment adept, etc...). Do you roll initiative before he casts? If the target passes his save, the target doesn't even know it was the target of a spell. If the target fails his save, there's no indication of hostile action, and thus no combat. So there's no argument here that combat even starts. But if the spellcaster instead imperceptibly casts fireball, then how could combat start because of that casting? There's no perceptible difference between fireball and dominate person until the fireball explodes. This has to be adjudicable without knowing what spell is being cast, because in-world the "enemies" don't know what spell is being cast (or even that a spell is being cast).
What you think the rules require is a narrative trainwreck and more corrosive to causality than a time travel plot device. Fortunately, the rules don't require any such thing. The DM is empowered to wait to roll initiative until combat has actually started.
My insistence on causality being linear and the narrative making sense is not my problem with the rules, it's a problem with your interpretation of the rules. As I note, the DM decides when combat starts. There is no obligation to call for initiative when you say there is. So my interpretation is fully rules compliant. The rules aren't the problem, your understanding of when you roll initiative is the problem.
I welcome anyone to point out any issues my interpretation creates, because I don't believe there are any.
And I'm sorry, but how would you define 'fighting a creature' that wasn't 'be in combat with that creature'? There's no difference to be drawn there; it's tautological: you're fighting it immediately upon rolling initiative. (I presume here that casting charm person is what 'started the combat', so the target is included in the group that is now classed as 'enemy' by construction, and not just a random bystander.)
(BTW, it's not even metagaming under your interpretation of the rules. Constructing scenarios where the aggressor is unperceived, and can simply neglect to take hostile action if they don't win initiative, is trivial -- and what ambusher would proceed with an ambush if they thought their victims had become alerted to them, but could withdraw or stay hidden without issue if they don't proceed? It's the sensible in-character decision to wait for a better opportunity.)
I think I said something similar in how I'd interpret the rules for when the DM decides initiative is rolled.
Also, if you agree the act of casting a spell shouldn't be enough to roll initiative, then you agree that (if creatures don't perceive the act of casting itself as hostile) it doesn't matter what spell is being cast, and would thus be the results of spellcasting which would potentially start combat after the spell has gone off.
Edits: fixing typos
In the odd case that you're surprised by combat starting but acting first in turn order, i don't have an issue explaining it with an intuition or danger sense if you haven't yet perceived an imminent threat.
You can still move, Dodge, use Magic, Ready an action of some sort, Search for concealed creatures, or attempt to Attack one by targeting it's location for example.
My take on this has evolved somewhat over the time I've spent thinking about it. I'm now probably going to use Ready out of combat to deal with situations of surprise beyond DIS on initiative. That is, if you want to actually act before someone and are planning on initiating combat (standard ambush scenario), then they Ready an attack with a appropriate trigger. As long as it isn't a spell, they can simply Ready until the trigger happens, no matter how long it takes.
Now, combat starts, initiative is rolled, and then the first thing to happen is the Readied action (using the creature's Reaction). All initiative flows from there.
I think lowers the power of the "surprise round" sufficiently while still making narrative and mechanical sense.
How can you be 'surprised by combat starting' if combat hasn't even started yet?
You can be suprised by combat starting at the start of combat when Initiative is rolled when no spell or attack was made yet as the rules explained.