Question About Initiative in Surprise Situations

Quote from Plaguescarred >>

Quote from Squirrelloid >>

Quote from Plaguescarred >>

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.

 The rules say the DM determines when combat starts and initiative is rolled.  Why would you decide combat has started while one side is unaware the other side is taking hostile action?

The relevant text from the 2024 DMG is:

Combat starts when—and only when—you say it does. Some characters have abilities that trigger on an Initiative roll; you, not the players, decide if and when Initiative is rolled. A high-level Barbarian can’t just punch their Paladin friend and roll Initiative to regain expended uses of Rage.

I am going to agree with Squirreloid that this text supports his position that the DM determines when combat starts and when Initiative is rolled is correct. Now, because the DM makes this determination, different DMs can have their own positions, and so choosing to roll initiative the second someone takes an action which could start combat is also valid, even if it means the surprised party could roll above the attacker despite disadvantage. 

Even though either method is valid by the rules, I also agree with Squirreloid that a good Initiative roll should not negate a failure to perceive the threat, and that surprised people acting in reaction to an event which has not happened does not make sense. That could result in things such as an unaware person who was the target of a hidden assassin using their action and movement to get to total cover before the assassin can take the shot which triggered initiative. Thus the assassin would not take the shot, so there would be nothing to trigger the initiative roll in the first place.

EDIT: And if the assassin in this case is a PC going for an NPC, imagine how the player would feel if after carefully planning their attack and being undetected, the DM told the player that their target "suddenly got an instinctive feeling" and arbitrarily dashed out of sight before the attack roll even happens due to a poor initiative roll.

Quote from Plaguescarred >>

Surprising a creature may result Advantage to Initiative if you're Invisible, which is most often the case when hidden for example.

What you are describing here is not actually the surprise mechanic for the game.  That is a named feature of the Invisible condition which could have been called anything but just happens to be named "surprise".  You are not required to actually surprise an enemy in order to take advantage of this feature. 

Quote from Squirrelloid >>

Quote from Plaguescarred >>

Quote from Squirrelloid >>

Quote from Plaguescarred >>

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.

 The rules say the DM determines when combat starts and initiative is rolled.  Why would you decide combat has started while one side is unaware the other side is taking hostile action?

 Because everyone rolls Initiative when combat start and If a combatant is surprised by combat starting, that combatant has Disadvantage on their Initiative roll.  

5.5E purposefully did away with free turn during Surprise where only one side can act as explained in Converting to SRD v5.2.1. 

Surprise [Revised Rule] Being surprised no longer deprives you of the ability to act on your first turn of combat. Instead, being surprised causes you to have Disadvantage on your Initiative roll.

In any situation where a character’s actions initiate combat, you can give the acting character Advantage on their Initiative roll as stated in the DMG.

Granting free action before Initiative is rolled and everyone take turns is not supported by the rules but was even counterindicated by Devs.

DM can of course rule otherwise but it makes Surprise more powerful than intended.