- Spawns an egg familiar, which cracks and turns into a random friendly enemy when Isaac is hurt.
- The egg regenerates upon entering a different room.
- The usefulness of the enemy depends on how many rooms have been cleared without getting hurt.
- For Greed Mode and Greedier Mode, the usefulness of the enemy is based on waves cleared rather than rooms.
- The list of available monsters is as follows:
- BFFS!: The enemy spawned will be a champion variant and egg grows in size.
- Eraser: Enemies erased by Eraser will never show up again, hindering Mystery Egg should it spawn said removed enemy.
- Holy Mantle: Losing the Mantle will not cause a friendly enemy to spawn.
- Mystery Egg is based on this Steam Workshop item by Strawrat and Aczom.
|Bug!||When using Extension Cord with Mystery Egg, after the egg turns into a friendly enemy, the electricity shoots out into a random corner of the room.|
|Bug!||When egg turns into a friendly Heart (Mask + Heart) will sometimes act as the heart companion for a mask already in the room resulting in an unbeatable room.|
Mystery Egg's appearance in the original steam workshop mod.
|The Binding of Isaac: Rebirth|
|Achievements||Attributes||Bosses||Cards and Runes||Challenges||Chapters|