A cluster of red cellular flesh.
Effect[]
Makes a fetus grow on the side of Isaac's head.
Increases available maximum Heart Containers by one and heals one and a half-hearts.
In original Binding of Isaac, it also increases Shot Speed by 16%. However this effect is removed since Rebirth.
Trivia[]
- Stem cells are an undifferentiated cell of a multicellular organism that is capable of giving rise to indefinitely more cells of the same type, thus why another human is growing out of Isaac.