×I really don't see anything that I can do to get the seep to behave. Unless I'm missing something, it's impossible to get a rock golem to trigger the seep's release plate, and there's no other enemy that I can get into that area. Never mind feeding the golem to the adder afterwards.

I've managed to do some clever stuff with the soldier (1,22) and decoy (31,26; facing NE) to keep everything I need alive, but I can't get the slayer to do his job while the soldier is still alive. Obviously using the soldier to pin the seep down is unintended, since the point is to not activate the horn in the first place, but it's the only way I've found to prevent the seep from getting stuck.

And yes, I'm pretty sure I know where the decoy is actually supposed to go in the intended solution. (31,26) allows the decoy to keep the aumtlich alive and stun it on the plate,
so if I'm allowing a soldier to spawn anyway, it seems to be the best spot to go.

×If the yellow doors on the north path were all open, the seep would take the south path instead.

Of course, the pressure plate that lets the seep move at all also closes the doors, and you can't open them again without killing the brain. And by the time you killed the brain, the seep would already be trapped.

×What you do with the wraithwing at the end is a little unintended, but not actually a break since it requires doing what I wanted anyways. All you had to do was hide in the shallow water outside of eye range. Actually, I'm kind of tempted to enforce what you did, because it's cool.

...and in fact, I think it's enforced if I just remove the hot tile directly in front of the eye, without breaking your demo at all or adding weird mechanisms. It breaks my demo and Aquator's, but only after most of the work has been done so it's not too hard to restore to a checkpoint to produce a working demo.

I would be very surprised if this introduced a major unintended solution, since only the eye and wraithwing can possibly move onto that tile. The rest of the chamber is still blocked off to puffs. Releasing the eye early would let you keep a puff out without killing the wubba, but it would remain stuck by the eye by the time you could get over there, and you wouldn't have a way to kill the eye anyhow.

At worst there might be some way to kill the eye without the wraithwing, but I'm okay with taking that risk if the rest of the room holds up. Going to submit to HA now.