Keys are pickups mainly used to open up locks, such as locked doors or certain types of Chests.

Epiphany introduces 1 type of Key into the game.

Multitool

Multitools are a special variant of keys. As long as the player has at least one Multitool, the key icon in the player's key count will be replaced by that of a Multitool icon, and holding down the drop key (CTRL for keyboard users) nearby a locked object will consume a Multitool and open it. Multitools can open up almost any type of locked "thing" in the game, including those that normally aren't opened with keys such as the doors to Challenge Rooms, entrances to Secret Rooms, doors within uncleared rooms, and so on.

Multitools are unlocked by defeating Mega Satan as Tarnished Cain, and have a 2% chance of replacing any normal key.

Notes

Multitools cannot open the following:
- Mega Satan's door
- Red Room doors (even if Red Key or a Cracked Key is held)
- The entrance to the Boss Rush
- The entrance to ???/Blue Womb
Multitools will become a Giga Bomb when using a Bombs are Key pill. This means that the opposite is also true and Giga Bombs will be turned into Multitools.