Why horror?

[Acies]

With HPL2 you could do the rolling barrels, have platforms appear out of nowhere after an event, do minor boss battles, but entity-to-player collision detection (i.e. "picking up" items as you run over them, getting hurt by rolling objects, et cetera) is not actually possible. Sure, you can have areas placed on top of each and every item and check to see if the player entered the area, and have areas placed in the path of the rolling objects and see if both the player and the object are in the area at the same time, but that is impractical.

I think the entityCollide applies to entities as well (I'm quite unsure but haven't Apjjm made it work?) - so the things you just described would be possible actually. You might even incorporate power-ups such as speed boosts, increased jumping, life regeneration (by timers), invincibility etc. I do feel that platforming is somewhat limited due to the reason that you may not change course once airborne. If you have played counterstrike and know bunny-jumping amnesia feels quite limited in comparison.