in the hotel area at ff1 you can open and jump into the dumpster to hide from npcs. (i think that only works with drg npcs)

The floor in pitfalls is removable so you can trap npcs with it.

In the office in the kv31 chamber there is a button that lets you close the gate.

the door in pitfalls lead to a dead end so don't use that unless necessary.

Don't bhop in the pattern area in ff1.