In-game pickup line
“Regen!”
Mechanics
What Stem Cell does
- In Repentance, entering a new floor heals half of Isaac's missing Red and Bone Hearts.
- It restores at least half a heart when healing is possible.
Achievement #301
How to unlock it
Defeat Ultra Greedier as Samson.
Unlocking an item and finding it during a run are separate steps.
Explore more unlocksIn a run
Practical note
Carry it across a floor transition when you have empty red or bone health to refill.
Reference
Game data and sources
The trinket ID, icon, game-file tags, and short pickup line come from the extracted Repentance files. This effect explanation is an editorial summary checked against the references below. Repentance+ can differ.
