Chaos, Chaos!

Hewwo! I'm making a multi-room trap that includes a random-effect-generator to make things more interesting (roll a d12 at the top of the round, affect the players/battlefield in some way), but I need some help coming up with effects. I'm not really looking for straight damage, more modifiers.

Plz help!

Tiny room/large guests - Everyone increases by 1 size. It’s probably gonna work best in an area with tight corridors and wider rooms for the squeeze rules to come into play.

Make every creature in the combat roll randomly to determine which of the 6 walls of the room is now the floor for them. Separates the fighters and casters - could be beneficial, could be a problem!

Everyone who touches the Macguffin becomes bright red. Seems innocent, then the Gorgon is released.

Is it cake? Only a roll when you go to use it will tell! That isn't your only sword, is it?

I used to do a big battlefield shake up. On a grid, roll a d8 for direction and a d6 for number of squares. I never made anyone go prone, just if you hit a wall or another creature, you stop. Good guys and bad guys alike. Sometimes it helps, sometimes it hurts. You never know.

Maybe the room starts spinning and tosses everyone around, making it hard to reach the door. (Spinning every direction, not just one, so fast you're almost weightless - almost)

Illusory pit, and a real pit covered by an illusion, that lead to random other rooms and separates the party.

Time pressure solve some sort of puzzle while the room fills with oil, and if they get it wrong, the oil is set aflame. (This one is a bit hardcore, so it would depend on table if you want to use it)

Floor slowly raises to the ceiling to complicate a battle, like a reverse ceiling crusher.

Room is a mimic.

A magical barrier of some sort splitting the room into sections (think Naboo reactor ray shields) that cycles on/off