What we need is an RNG mech.
Kind of like AI War for people who don't play AI War?
random starting weapon
Currently possible, but it would be rerolled from room to room. In this case, probably ok in theory, but in practice it probably conflicts with the switching-room logic.
enemies have a chance of dropping items
I don't know if that's possible or not, in terms of having it be conditional on what mech you picked. I guess you could have the player's shots have a % chance of copying modifiers to the enemies that would make them drop things. Haven't checked if that works or not.
or a chance of dropping other enemies (and that just gave me ideas)
Hahaha. Possibly a chance each kill of applying a world-wide modifier to spawn rate (which is what the Creator ability uses to increase the spawns).
chance of getting double health from healing items
Possible, if relatively mundane.
but also a chance of just exploding....
That's how you know it's on.