Playing as Eve. Used a telepill on an earlier floor, red key got changed to a glitched item and the trigger seems to be familiar damage adds a soul heart but also spawns Damocles.

Goddammit I love that effect

How did the run go?

Ended up completing my goal of Mother, so that was excellent. Used the razor blade + infinite soul hearts to make short work of her.

Other good items included, chocolate milk, Jacob's ladder and polyphemus.