I managed to get myself stuck in the first gate as I attempted to run through, and wasn't able to escape its vice grip.

Genocide%: Kill any and all NPCs in every level, yes, even the Nullrats. Infinitely spawning enemies (such as the hordes in Time Tower and Throneroom) are exempt.

Sourceruns%: Complete the game by bunnyhopping backwards.

Buttonmasher%: Press all the buttons in the Museum as fast as possible.

One in the Chamber%: In order to use a gun, you must chamber a round and eject the magazine immediately after.

EmptyMag%: Softlock yourself in the Breakroom as fast as possible

Not anymore