Of course you can do this. Absolutely trivial. The mounted combat rules, such as they are, explicitly allow you to ride a larger creature into combat, and you can explicitly dictate your defender's body shape, meaning you can leave a cavity inside it large enough for the artificer and leave eye-holes. Creation bards can make a mech suit (theirs can fly!) out of a wardrobe in a similar fashion, and NPCs can do something akin to it, too - an ogre howdah has 4 goblins inside the ogre's map space.
Can you please tell us the page which has the rules for "have the chest be a hollow cockpit and cover it in metal plating to prevent attacks from passing through. This would give you full cover from attacks"?
I'm not following what exactly you want a citation for.
A page that backs up your claim that what the OP wanted is something that "Of course you can do this. Absolutely trivial." And, if you missed it the first two times, what OP wanted was "have the chest be a hollow cockpit and cover it in metal plating to prevent attacks from passing through. This would give you full cover from attacks". Could you please provide us a page number for where it says you can do that?
Can you ride inside a ship, or is one required to stay above decks, regardless of ship design? If 'yes,' then 'riding' does not automatically mean 'on.'
When you are riding inside a ship, i.e. below decks and not looking out a porthole, do you or do you not have full cover from any attacks coming from outside the ship?
But wait, you say. This is a creature, not a ship. So, in anticipation of that question, if you are behind a large enough creature, say, a dragon or something similarly massive, do you or do you not have full cover against any attacks coming from 180 degrees the other side of the dragon? If not, why not?
Not sure what any of these has to do with what I wrote about. Are you suggesting there are rules for being inside a dragon, controlling it? Or do you mean that you can control the dragon by standing next to it or that, if you stand next to the dragon you have full cover from the thing on the other side of it but the thing on the other side of it doesn't have full cover from you? I'm a bit confused as to what point you're trying to make and how it is relevant to OP's question.
Pardon, but we are not talking about being inside dragons. The dragon example was to show that creatures can constitute full cover. Comparing not being able to be inside a dragon with not being able to, size permitting, be inside an appropriately designed steel defender is like saying that since you cannot go below deck in a dinghy, you cannot go below deck on a ship of the line. Both those are water vessels (analogous to both the Dragon and Steel Defender being creatures) but one has a below deck to go to and the other does not.
Yeah, I know. But your posts was so confused that I had to ask what point you were trying to make. But I guess that we agree that if you are in full cover from something, that thing is also in full cover from you (the goblin on the other side of the dragon can't see you and you can't see the goblin) which means that what OP suggested (being inside the SD to gain full cover) doesn't work as presented?
Pardon, but we are not talking about being inside dragons. The dragon example was to show that creatures can constitute full cover. Comparing not being able to be inside a dragon with not being able to, size permitting, be inside an appropriately designed steel defender is like saying that since you cannot go below deck in a dinghy, you cannot go below deck on a ship of the line. Both those are water vessels (analogous to both the Dragon and Steel Defender being creatures) but one has a below deck to go to and the other does not.
Yeah, I know. But your posts was so confused that I had to ask what point you were trying to make. But I guess that we agree that if you are in full cover from something, that thing is also in full cover from you (the goblin on the other side of the dragon can't see you and you can't see the goblin) which means that what OP suggested (being inside the SD to gain full cover) doesn't work as presented?
That, plus air supply, plus having to move by grapple rules or only on the steel defender's turn (which would preclude most actions)..... technically works but way too many flaws to be of any actual use.
Exactly. Thank you for the clarification. Glad we could sort out the confusions.
Of course you can do this. Absolutely trivial. The mounted combat rules, such as they are, explicitly allow you to ride a larger creature into combat, and you can explicitly dictate your defender's body shape, meaning you can leave a cavity inside it large enough for the artificer and leave eye-holes. Creation bards can make a mech suit (theirs can fly!) out of a wardrobe in a similar fashion, and NPCs can do something akin to it, too - an ogre howdah has 4 goblins inside the ogre's map space.
Can you please tell us the page which has the rules for "have the chest be a hollow cockpit and cover it in metal plating to prevent attacks from passing through. This would give you full cover from attacks"?
First of all, have any of you read the full cover rules? If a creature is completely concealed by an obstacle, which in this case, is our steel defender they have full cover. Simple as that. And for seeing outside the defender, you can have a windshield of sorts. You also wouldn't suffocate if you make a few air vents. And for controlling the mech, it specifically says it obeys your commands, which can be narrated as a control panel or something.
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Hollow unbreakable arrows are the most OP common magic item, and my current method of coming up with insane combat shenanigans.
if you make a steel pipe with one end closed and a nozzle on the other, you can enlarge it, fill with any liquid, and then drop concentration, creating a high pressure squirt gun. (or a pipe bomb, depending if it holds)
So, maybe we should ask ourselves, why would anyone NOT do this, if it is indeed allowed? And if it's really that useful, then why isn't it specifically called out as one of the primary functions of the feature?
So, maybe we should ask ourselves, why would anyone NOT do this, if it is indeed allowed? And if it's really that useful, then why isn't it specifically called out as one of the primary functions of the feature?
Well, if you could see out (windshield, port hole, or something) I could see it working really no differently than normal. You take your action and bonus action command it. Only thing would be if you needed clear unobstructed path for a spell or other action, same as if you wanted to cast a spell through a glass window. It’s still considered cover and some spells need the clear path so casting through your SD port hole wouldn’t work.
But for me, if I was DM I might not allow it. Next you will have players wanting to make “tower” shield that they can carry as portable full cover. I don’t think they are in 5E for a reason.
Well, if the window is part of the creature's body, which it is, and if the window is articulated, which I see no reason it can't be, then the creature can open the window as easily as opening its mouth, and close it the same way. You may need to ready your action to interact with the outside world during your Steel Defender's turn, when it does this for you. Which would make concentration spells more awkward, but not devastatingly so. The pattern of "ready to cast my concentration spell, cast it, then cast cantrips for the remainder of the fight" isn't an uncommon one.
I think it's probably important to know what happens if your Steel Defender dies while you're inside it. Like, can you get out? If so, how -- and does it take an action? I don't think anyone will be able to hit me with a rule here, and I think that's a strike against this idea.
Edit: By the way, what's the Battle Master got to do with this?
So, maybe we should ask ourselves, why would anyone NOT do this, if it is indeed allowed? And if it's really that useful, then why isn't it specifically called out as one of the primary functions of the feature?
Well, if you could see out (windshield, port hole, or something) I could see it working really no differently than normal. You take your action and bonus action command it. Only thing would be if you needed clear unobstructed path for a spell or other action, same as if you wanted to cast a spell through a glass window. It’s still considered cover and some spells need the clear path so casting through your SD port hole wouldn’t work.
But for me, if I was DM I might not allow it. Next you will have players wanting to make “tower” shield that they can carry as portable full cover. I don’t think they are in 5E for a reason.
1) Air
2) How do you 'Take your action?' Fitting inside it does not equate to free movement within it as if you were outside it. There is zero provision for that. The only way to move another creature is via the grapple rules and that does not equate to manipulating it like a puppet.
1. I assume some kind of vent or air holes. So you won’t be swimming underwater in this way.
2. cast a spell. Probably the only or at least primary option. Don’t need to move for that if you are already on range. Other actions like dash or disengage would not be available as you would be completely reliant on the SD. Just as if you are riding a horse. Of course this makes some of you other features useless while inside, like extra attack, martial weapon proficiencies.
Choir, I could see opening a window or hatch but some DM’s might consider opening or closing an object interaction so ymmv using this approach. And how big is said window to give you enough room to accurately reach out and attack with a weapon like a shortsword? Maybe if you had a crossbow with repeating infusion?
Late to this discussion - but it is a fun idea! Having said that, I would probably consider there to be significant pros and cons to being inside the SD
Pros:
Full cover? Maybe - although material wise 3/4 cover would seem more reasonable since trying to encase the artificer in totality probably would not leave enough materials for moving limbs etc.
Damage absorption - I would probably run it that opponents simply attack the SD first, and so all damage is absorbed by the SD - which is fine as long as it stays up. But once it drops, you'd be trapped inside.
Cons:
Being inside the cavity would be akin to being restrained. I don't see the artificer being able to carry out many actions in there? Perhaps verbal spells would be ok, but I don't see how there would be space to both provide adequate cover as well as open enough to allow attacks. So your own action economy would probably be severely hampered - which at the end of the day might mean it's simply not worth it.
1) If there are vent holes, is it still full cover?
2) Verbal only. You cannot make intricate hand gestures (or even focus gestures) when sealed into such a cramped space.
1) Yes, absolutely. Houses aren't air tight and yet their walls provide full cover. This is not one of the many flaws with this idea. I suggest focusing energy on one of those.
2) It totally didn't occur to me that this would require squeezing rules, but I suppose it will. Not that it really matters if every target has full cover from your spells, but weird and very clunky work arounds for that (that DMs can easily prevent since there are no rules allowing them anyway) are starting to pop up.
I guess it depends on the design of the SD to determine if the space is too cramped to gesture. I mean, you can still cast spells while restrained. If it’s kind of like a barrel with legs and head you might have more space to work with. There are no rules for the inner workings of the SD so would be a DM decision on if you can gesture well enough.
And as far as what happens if the SD dies I would say it takes your action to get out of it.
1) If there are vent holes, is it still full cover?
2) Verbal only. You cannot make intricate hand gestures (or even focus gestures) when sealed into such a cramped space.
1) Yes, absolutely. Houses aren't air tight and yet their walls provide full cover. This is not one of the many flaws with this idea. I suggest focusing energy on one of those.
2) It totally didn't occur to me that this would require squeezing rules, but I suppose it will. Not that it really matters if every target has full cover from your spells, but weird and very clunky work arounds for that (that DMs can easily prevent since there are no rules allowing them anyway) are starting to pop up.
1) Houses have a lot more space in them. You could just as easily say 'But the planet Earth has an atmosphere with finite limits, so why doesn't everyone suffocate?' The situations are very different. Plus inside a house you are likely not by an open window. If you are standing in front of an open window, the house does not provide full cover.
2) Not sure how many DM's would allow somatic components while squeezed into someplace.
1. Soffits houses get ventilation without an open window
1) If there are vent holes, is it still full cover?
2) Verbal only. You cannot make intricate hand gestures (or even focus gestures) when sealed into such a cramped space.
1) Yes, absolutely. Houses aren't air tight and yet their walls provide full cover. This is not one of the many flaws with this idea. I suggest focusing energy on one of those.
2) It totally didn't occur to me that this would require squeezing rules, but I suppose it will. Not that it really matters if every target has full cover from your spells, but weird and very clunky work arounds for that (that DMs can easily prevent since there are no rules allowing them anyway) are starting to pop up.
1) Houses have a lot more space in them. You could just as easily say 'But the planet Earth has an atmosphere with finite limits, so why doesn't everyone suffocate?' The situations are very different. Plus inside a house you are likely not by an open window. If you are standing in front of an open window, the house does not provide full cover.
2) Not sure how many DM's would allow somatic components while squeezed into someplace.
1. Soffits houses get ventilation without an open window
Yeah, for example.
I honestly have no idea what Kotath's counter argument is. You don't need an open window to let air in. If I locked myself in a closet with no windows, I would not be in any danger of suffocation and no attacks could hit me through the total cover (not even through the seem of the door frame).
Like I said, there are multiple flaws with this idea, but full cover suffocating you is not one of them.
I guess it depends on the design of the SD to determine if the space is too cramped to gesture. I mean, you can still cast spells while restrained. If it’s kind of like a barrel with legs and head you might have more space to work with. There are no rules for the inner workings of the SD so would be a DM decision on if you can gesture well enough.
And as far as what happens if the SD dies I would say it takes your action to get out of it.
Heavy armor takes 5 minutes to doff, 2 and a half if you have help, and it was designed to be disassembled and removed easily.
Personally I would treat this idea as simply a reflavoring of mounted combat and leave it at that. It keeps things simple and gives clear answers for the myriad of questions that can be easily understood by all the Players at the table.
All of the questions that have been raised and answered in this thread show how much needs to be considered and debated and it is just scratching the surface. Thankfully the Steel Defender is immune to the Charmed condition, but what happens to the player inside if the Steel Defender is Frightened, Stunned, Paralyzed, Petrified, or Incapacitated? What about all the waste heat generated by Steel Defender, how is it dissipated? Can you also wear armor or does the Steel Defender prevent that? What about a shield, weapon, or other held objects?
For those that want to treat the player as having total cover, why not just build a 5ft hollow cube out of wood or some other material and strap it to a Draft Horse? This could be done for probably less than 100gp and can be accomplished by any class. Give the cube a door and an arrow slit and you are good to go. This has the same effect as giving the character inside total or 3/4 cover and it is much easier to conceive of how it would work.
Of course you can do this. Absolutely trivial. The mounted combat rules, such as they are, explicitly allow you to ride a larger creature into combat, and you can explicitly dictate your defender's body shape, meaning you can leave a cavity inside it large enough for the artificer and leave eye-holes. Creation bards can make a mech suit (theirs can fly!) out of a wardrobe in a similar fashion, and NPCs can do something akin to it, too - an ogre howdah has 4 goblins inside the ogre's map space.
Can you please tell us the page which has the rules for "have the chest be a hollow cockpit and cover it in metal plating to prevent attacks from passing through. This would give you full cover from attacks"?
First of all, have any of you read the full cover rules? If a creature is completely concealed by an obstacle, which in this case, is our steel defender they have full cover. Simple as that. And for seeing outside the defender, you can have a windshield of sorts. You also wouldn't suffocate if you make a few air vents. And for controlling the mech, it specifically says it obeys your commands, which can be narrated as a control panel or something.
We have adressed to issues already. If you have full cover from something, that something has full cover from you. I have also provided alternative ways to actually make your suggestion work that is within the rules.
I guess it depends on the design of the SD to determine if the space is too cramped to gesture. I mean, you can still cast spells while restrained. If it’s kind of like a barrel with legs and head you might have more space to work with. There are no rules for the inner workings of the SD so would be a DM decision on if you can gesture well enough.
And as far as what happens if the SD dies I would say it takes your action to get out of it.
Heavy armor takes 5 minutes to doff, 2 and a half if you have help, and it was designed to be disassembled and removed easily.
Personally I would treat this idea as simply a reflavoring of mounted combat and leave it at that. It keeps things simple and gives clear answers for the myriad of questions that can be easily understood by all the Players at the table.
All of the questions that have been raised and answered in this thread show how much needs to be considered and debated and it is just scratching the surface. Thankfully the Steel Defender is immune to the Charmed condition, but what happens to the player inside if the Steel Defender is Frightened, Stunned, Paralyzed, Petrified, or Incapacitated? What about all the waste heat generated by Steel Defender, how is it dissipated? Can you also wear armor or does the Steel Defender prevent that? What about a shield, weapon, or other held objects?
For those that want to treat the player as having total cover, why not just build a 5ft hollow cube out of wood or some other material and strap it to a Draft Horse? This could be done for probably less than 100gp and can be accomplished by any class. Give the cube a door and an arrow slit and you are good to go. This has the same effect as giving the character inside total or 3/4 cover and it is much easier to conceive of how it would work.
I pretty much agree with the bolded and I said similar in an earlier post (#12). Would be the easiest and balanced option.
As far as the other conditions, the character controls the SD with their bonus action. If they suffer from one of the conditions you mentioned then they possibly cannot use their BA and the SD takes the dodge action (I think that's their default). Frightened they couldn't command the SD to move closer and have the disadvantages. Stunned, pretty much as the condition with the exception of advantage on attacks against them as they are in full cover. Paralyzed, Petrified, Incapacitated would be as the condition, and the SD can only do default action (Dodge) until the character recovers.
I don't think getting out would take as long as doffing armor, as it probably has a hatch of some sort to enter/exit. You're not actually donning the SD as armor. Just riding inside it.
Heat generated by the SD is completely DM dependent. Nothing in the SD description mentions heat.
@Kothath - I get it. You're imagining Iron Man, but the rest of us are imagining Mobile Suit Gundam. Just make the inside bigger. As many problems as this concept has, suffocation doesn't need to be one of them. The Artificer only needs about one combat's worth of air in there anyway.
And in any case, you could just put the ventilation ducts on the top, or conceal them with armor, or make them small enough that nothing dangerous gets in. They don't have to be straight lines either. You can certainly have full cover and an air supply. *If* you accept that "determine its appearance" accounts for all this nonsense.
A more direct visual would be the Lagann machine from the cartoon Tengen Toppa Gurren Lagann. I think its size kind of varies with the animation, but it's not that big. (The first machine they get. Simon's machine.)
Not sure what some of those are but I’m thinking along the lines of a smaller version of the Apparatus of Kwalish. It seems like something like that would have more room to gesture for spells. But you wouldn’t be able to make melee attacks yourself.
And I don’t understand the hang ups with ventilation. All sorts of twisty turny pipes can vent air in or out without giving direct LoS to the person inside. It’s pretty much a non-issue.
A more direct visual would be the Lagann machine from the cartoon Tengen Toppa Gurren Lagann. I think its size kind of varies with the animation, but it's not that big. (The first machine they get. Simon's machine.)
Edit: And Simon is bigger than a gnome.
The Gurren in that series are all tech based mecha, so things like air filtration or even self contained air recycling are options that are not merely appearance based. And there is not that much room to move around in that thing. He is seated and cannot really stand up without opening it up. He cannot reach particularly forward. These issues would likely limit gestures materially. And he is a 14 year old, 5'.
Yeah, exactly. That's all fine. There's no problems here. The roof pops open and he can shoot a crossbow or whatever, then close it. The machine depicted there is even larger than it technically needs to be for our purposes -- the whole crew gets crammed in it for comic effect, plus Simon is bigger than a Small creature, so a similarly designed Steel Defender for use by a gnome could conceivably be Medium sized.
It's been a while since I watched it but I don't really remember there being any discussion of air systems. But the point remains: tiny gaps such as those that exist between the door of a closet or the plates of a suit of armor can surely permit air flow without having to compromise the existence of full cover.
@Kothath - I get it. You're imagining Iron Man, but the rest of us are imagining Mobile Suit Gundam. Just make the inside bigger. As many problems as this concept has, suffocation doesn't need to be one of them. The Artificer only needs about one combat's worth of air in there anyway.
And in any case, you could just put the ventilation ducts on the top, or conceal them with armor, or make them small enough that nothing dangerous gets in. They don't have to be straight lines either. You can certainly have full cover and an air supply. *If* you accept that "determine its appearance" accounts for all this nonsense.
Steel Defenders is a Medium construct, so nowhere near Gundam sized. "Just make the inside bigger..." There isn't unlimited space to make it bigger.
Make the vents too small and they do not let enough air in or get clogged. And again you do not have unlimited surface area. Open top design? Good luck if it rains. "Determine its appearance" does not equate to there being a practical design.
Will you please stop arguing about air as if it needs a 6 inch diameter hole to flow. A few grates at the bottom will provide more than enough air flow while still providing full cover from every direction. This is the least problem of all it's problems.
A cabinet provides full cover and you won't suffocate in it. People don't suffocate in elevators when the power goes out. Breathing is not an issue with this idea, stop distracting away from the actual reasons this doesn't work.
The problem with this idea is that the driver/passenger is as relevant to battle as the contents of a backpack. Other than giving commands, you can't affect the battlefield. If you want to rolepaly a gnome in a mech suit, might I suggest a warforged.
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Yeah, I know. But your posts was so confused that I had to ask what point you were trying to make. But I guess that we agree that if you are in full cover from something, that thing is also in full cover from you (the goblin on the other side of the dragon can't see you and you can't see the goblin) which means that what OP suggested (being inside the SD to gain full cover) doesn't work as presented?
Exactly. Thank you for the clarification. Glad we could sort out the confusions.
Have a good one. B)
First of all, have any of you read the full cover rules? If a creature is completely concealed by an obstacle, which in this case, is our steel defender they have full cover. Simple as that. And for seeing outside the defender, you can have a windshield of sorts. You also wouldn't suffocate if you make a few air vents. And for controlling the mech, it specifically says it obeys your commands, which can be narrated as a control panel or something.
Hollow unbreakable arrows are the most OP common magic item, and my current method of coming up with insane combat shenanigans.
if you make a steel pipe with one end closed and a nozzle on the other, you can enlarge it, fill with any liquid, and then drop concentration, creating a high pressure squirt gun. (or a pipe bomb, depending if it holds)
So, maybe we should ask ourselves, why would anyone NOT do this, if it is indeed allowed? And if it's really that useful, then why isn't it specifically called out as one of the primary functions of the feature?
Well, if you could see out (windshield, port hole, or something) I could see it working really no differently than normal. You take your action and bonus action command it. Only thing would be if you needed clear unobstructed path for a spell or other action, same as if you wanted to cast a spell through a glass window. It’s still considered cover and some spells need the clear path so casting through your SD port hole wouldn’t work.
But for me, if I was DM I might not allow it. Next you will have players wanting to make “tower” shield that they can carry as portable full cover. I don’t think they are in 5E for a reason.
EZD6 by DM Scotty
https://www.drivethrurpg.com/en/product/397599/EZD6-Core-Rulebook?
Well, if the window is part of the creature's body, which it is, and if the window is articulated, which I see no reason it can't be, then the creature can open the window as easily as opening its mouth, and close it the same way. You may need to ready your action to interact with the outside world during your Steel Defender's turn, when it does this for you. Which would make concentration spells more awkward, but not devastatingly so. The pattern of "ready to cast my concentration spell, cast it, then cast cantrips for the remainder of the fight" isn't an uncommon one.
I think it's probably important to know what happens if your Steel Defender dies while you're inside it. Like, can you get out? If so, how -- and does it take an action? I don't think anyone will be able to hit me with a rule here, and I think that's a strike against this idea.
Edit: By the way, what's the Battle Master got to do with this?
1. I assume some kind of vent or air holes. So you won’t be swimming underwater in this way.
2. cast a spell. Probably the only or at least primary option. Don’t need to move for that if you are already on range. Other actions like dash or disengage would not be available as you would be completely reliant on the SD. Just as if you are riding a horse.
Of course this makes some of you other features useless while inside, like extra attack, martial weapon proficiencies.
Choir, I could see opening a window or hatch but some DM’s might consider opening or closing an object interaction so ymmv using this approach. And how big is said window to give you enough room to accurately reach out and attack with a weapon like a shortsword? Maybe if you had a crossbow with repeating infusion?
EZD6 by DM Scotty
https://www.drivethrurpg.com/en/product/397599/EZD6-Core-Rulebook?
Late to this discussion - but it is a fun idea! Having said that, I would probably consider there to be significant pros and cons to being inside the SD
Pros:
Full cover? Maybe - although material wise 3/4 cover would seem more reasonable since trying to encase the artificer in totality probably would not leave enough materials for moving limbs etc.
Damage absorption - I would probably run it that opponents simply attack the SD first, and so all damage is absorbed by the SD - which is fine as long as it stays up. But once it drops, you'd be trapped inside.
Cons:
Being inside the cavity would be akin to being restrained. I don't see the artificer being able to carry out many actions in there? Perhaps verbal spells would be ok, but I don't see how there would be space to both provide adequate cover as well as open enough to allow attacks.
So your own action economy would probably be severely hampered - which at the end of the day might mean it's simply not worth it.
1) Yes, absolutely. Houses aren't air tight and yet their walls provide full cover. This is not one of the many flaws with this idea. I suggest focusing energy on one of those.
2) It totally didn't occur to me that this would require squeezing rules, but I suppose it will. Not that it really matters if every target has full cover from your spells, but weird and very clunky work arounds for that (that DMs can easily prevent since there are no rules allowing them anyway) are starting to pop up.
I guess it depends on the design of the SD to determine if the space is too cramped to gesture. I mean, you can still cast spells while restrained. If it’s kind of like a barrel with legs and head you might have more space to work with. There are no rules for the inner workings of the SD so would be a DM decision on if you can gesture well enough.
And as far as what happens if the SD dies I would say it takes your action to get out of it.
EZD6 by DM Scotty
https://www.drivethrurpg.com/en/product/397599/EZD6-Core-Rulebook?
1. Soffits houses get ventilation without an open window
EZD6 by DM Scotty
https://www.drivethrurpg.com/en/product/397599/EZD6-Core-Rulebook?
Yeah, for example.
I honestly have no idea what Kotath's counter argument is. You don't need an open window to let air in. If I locked myself in a closet with no windows, I would not be in any danger of suffocation and no attacks could hit me through the total cover (not even through the seem of the door frame).
Like I said, there are multiple flaws with this idea, but full cover suffocating you is not one of them.
Heavy armor takes 5 minutes to doff, 2 and a half if you have help, and it was designed to be disassembled and removed easily.
Personally I would treat this idea as simply a reflavoring of mounted combat and leave it at that. It keeps things simple and gives clear answers for the myriad of questions that can be easily understood by all the Players at the table.
All of the questions that have been raised and answered in this thread show how much needs to be considered and debated and it is just scratching the surface. Thankfully the Steel Defender is immune to the Charmed condition, but what happens to the player inside if the Steel Defender is Frightened, Stunned, Paralyzed, Petrified, or Incapacitated? What about all the waste heat generated by Steel Defender, how is it dissipated? Can you also wear armor or does the Steel Defender prevent that? What about a shield, weapon, or other held objects?
For those that want to treat the player as having total cover, why not just build a 5ft hollow cube out of wood or some other material and strap it to a Draft Horse? This could be done for probably less than 100gp and can be accomplished by any class. Give the cube a door and an arrow slit and you are good to go. This has the same effect as giving the character inside total or 3/4 cover and it is much easier to conceive of how it would work.
We have adressed to issues already. If you have full cover from something, that something has full cover from you. I have also provided alternative ways to actually make your suggestion work that is within the rules.
I pretty much agree with the bolded and I said similar in an earlier post (#12). Would be the easiest and balanced option.
As far as the other conditions, the character controls the SD with their bonus action. If they suffer from one of the conditions you mentioned then they possibly cannot use their BA and the SD takes the dodge action (I think that's their default). Frightened they couldn't command the SD to move closer and have the disadvantages. Stunned, pretty much as the condition with the exception of advantage on attacks against them as they are in full cover. Paralyzed, Petrified, Incapacitated would be as the condition, and the SD can only do default action (Dodge) until the character recovers.
I don't think getting out would take as long as doffing armor, as it probably has a hatch of some sort to enter/exit. You're not actually donning the SD as armor. Just riding inside it.
Heat generated by the SD is completely DM dependent. Nothing in the SD description mentions heat.
EZD6 by DM Scotty
https://www.drivethrurpg.com/en/product/397599/EZD6-Core-Rulebook?
@Kothath - I get it. You're imagining Iron Man, but the rest of us are imagining Mobile Suit Gundam. Just make the inside bigger. As many problems as this concept has, suffocation doesn't need to be one of them. The Artificer only needs about one combat's worth of air in there anyway.
And in any case, you could just put the ventilation ducts on the top, or conceal them with armor, or make them small enough that nothing dangerous gets in. They don't have to be straight lines either. You can certainly have full cover and an air supply. *If* you accept that "determine its appearance" accounts for all this nonsense.
A more direct visual would be the Lagann machine from the cartoon Tengen Toppa Gurren Lagann. I think its size kind of varies with the animation, but it's not that big. (The first machine they get. Simon's machine.)
Edit: And Simon is bigger than a gnome.
Not sure what some of those are but I’m thinking along the lines of a smaller version of the Apparatus of Kwalish. It seems like something like that would have more room to gesture for spells. But you wouldn’t be able to make melee attacks yourself.
And I don’t understand the hang ups with ventilation. All sorts of twisty turny pipes can vent air in or out without giving direct LoS to the person inside. It’s pretty much a non-issue.
EZD6 by DM Scotty
https://www.drivethrurpg.com/en/product/397599/EZD6-Core-Rulebook?
Yeah, exactly. That's all fine. There's no problems here. The roof pops open and he can shoot a crossbow or whatever, then close it. The machine depicted there is even larger than it technically needs to be for our purposes -- the whole crew gets crammed in it for comic effect, plus Simon is bigger than a Small creature, so a similarly designed Steel Defender for use by a gnome could conceivably be Medium sized.
It's been a while since I watched it but I don't really remember there being any discussion of air systems. But the point remains: tiny gaps such as those that exist between the door of a closet or the plates of a suit of armor can surely permit air flow without having to compromise the existence of full cover.
Will you please stop arguing about air as if it needs a 6 inch diameter hole to flow. A few grates at the bottom will provide more than enough air flow while still providing full cover from every direction. This is the least problem of all it's problems.
A cabinet provides full cover and you won't suffocate in it. People don't suffocate in elevators when the power goes out. Breathing is not an issue with this idea, stop distracting away from the actual reasons this doesn't work.
The problem with this idea is that the driver/passenger is as relevant to battle as the contents of a backpack. Other than giving commands, you can't affect the battlefield. If you want to rolepaly a gnome in a mech suit, might I suggest a warforged.