This isn’t technically D&D, It’s a D&D-ish roleplaying game that I invented called “Monsters & Magic”, But I really need help. Ok, so soon the party will go into a room with a mechanical golem in the center and 4 snake statues, one on each wall of the room, And as soon as they party attacks the golem the door behind and in front of them will slam shut and they'll be trapped, also the snake's mouths will open revealing a tube that shoots different kinds of dangerous gases. On the statues turn it will shoot out a random kind of gas that affects the party but not the golem (Cause it doesn't need to breathe), The type of gas that comes out of the tube is determined by rolling a d6 and consulting a table that says what happens, but, I only have one type of gas that I've thought of so far and I need help coming up with the other five, The one I've come up with is a grey gas that makes your mind fuzzy and disoriented making it impossible to focus on anything, Making it so you can’t cast or use any magical spell or item. By the way this trap was inspired by the Poisoned Tempest trap from Xanathar’s guide to everything.

1) "Stinking Cloud" type gas- make a save or lose your turn, coughing, retching, whatever.

2) "Fog Cloud" type gas- the "it's not That bad" gas, makes it impossible to see

3) Flammable gas- on its own not That bad, just thins the atmosphere, which if it builds up 2 levels causes them to have to start making saves or suffer levels of exhaustion.  However the only way to clear it is the one thing they'd Really rather not do- ignite it.

4) Pure Air- Since if you don't have a "clearing" type gas, it Should be a TPK, since eventually the oxygen and clean air is going to run out.

5) Fear gas- since there's nothing quite like being locked in a trapped room with breathing being an issue, a golem in the middle out to kill you, and statues belching poison on the regular, it definitely needs that special something to make it memorable of some good old fashioned scarecrow gas.  Failing the one save makes you Frightened (of the golem and the statues, effectively locking you in place), failing again makes you paralyzed with fear.  More importantly this lets you Really amp up the descriptors and go all horror movie  on them.

There's 5, if you need more let me know, that was just off the cuff.  Good luck and enjoy!

Hmm, I like the stinking cloud idea, but the rest wouldn’t really work in the mechanics of the campaign I’m running. Sorry to ask this, but can you come up with a few more?

ok but I'm going to strongly double down on the idea that you really should have a "clear air" type gas unless you want a TPK, just saying :-)

1) Disorienting Gas - This messes with your sense of balance and has weird interactions with your inner ear.  Turns all terrain into difficult terrain and / or requires saving throws or falling prone upon attempted movement.

2) Hallucinatory gas- messes with your perceptions Big Time.  Afflicts the "confused" status, or makes them perceive their allies as hostile, or something to that effect.  It's a bad trip.

3) Tear gas- provides disadvantage on attack rolls and perception checks or otherwise negatively impairs combat abilities, it makes it difficult (and unpleasant) to do much of anything.

4) Toxic gas- Straight up poison damage.  Raw damage.  The stuff that'll just kill you.

5) Gas of unusual density- Makes the players "skate" above the floor as the gas is more dense than they are.  Over time could pin them against the ceiling if it fills the room.  Still incredibly difficult to move through unless you have a swim speed, or a fly speed, but different from a descriptor level.

That's all I've got without giving it actual thought :-)  If you need more let me know but it'll likely take hours or a day or something to come up with the next batch.  Hopefully at least a couple of those were usable.

I think there might be a bit of miscommunication, The gas doesn’t stack everytime it happens, It just has one effect, Then it goes away. What’s the “confused” condition? I can’t find anything about that on dndbeyond. I like the toxic gas idea, I think I’ll use it, I also came up with another one, The Vantablack gas, A pitch black gas that fills the room making it so you can’t see. If you could please think of 2 more that would really help me out.

Confusion:

An affected target can’t take reactions and must roll a d10 at the start of each of its turns to determine its behavior for that turn.

d10 Behavior
1 The creature uses all its movement to move in a random direction. To determine the direction, roll a d8 and assign a direction to each die face. The creature doesn’t take an action this turn.
2-6 The creature doesn’t move or take actions this turn.
7-8 The creature uses its action to make a melee attack against a randomly determined creature within its reach. If there is no creature within its reach, the creature does nothing this turn.
9-10 The creature can act and move normally.

What happens if the PCs don't attack the golem?

Quote from Auberginian >>

What happens if the PCs don't attack the golem?

I've figured out what the other gases are going to be, Thanks for helping me out with ideas.

Or they run away it isn't like a golem is.known for its speed. My point is you are creating a situation that requires a specific incident to enact it. And the more effort you spend designing it the more you get invested in it. Which is going to lead you to force a resolution that invokes your clever trap.

Quote from Auberginian >>

Or they run away it isn't like a golem is.known for its speed. My point is you are creating a situation that requires a specific incident to enact it. And the more effort you spend designing it the more you get invested in it. Which is going to lead you to force a resolution that invokes your clever trap.

Rather than just types of poison gas, make the heads alter the environment. One makes the room hot, causing the golem to be hot and do fire damage. In order to do damage or bonus damage to the golem, they have to turn to room to cold. After one round, the golem become cold, which is vulnerable to lightning. etc.  If they choose the wrong head, too bad. The heads randomly reset after they are used once.

The heads could change the floor plan into pits or gravel or water or whatever.

One head drops a school of piranha, another fills to room 3 feet of water, another drains all the water and the fish, can't think of anything for the fourth. The golem needs to be defeated by feeding it dead piranha.

Oh no wait. LIVE piranha would be better.

What the heck did I just read? Also, a group of piranhas is called a ”Shoal” not a school