The Binding of Isaac: Antibirth Wiki

Antibirth adds a few new types of pickups.


Immortal Heart

Immortal Heart.png

Immortal Hearts are white hearts which append to the end of the health bar like soul hearts.

Immortal Hearts always take two hits to be fully depleted, and will regenerate from half to full upon clearing a room.

Rotten Heart

Rotten Heart.png

Rotten Hearts are infested red hearts which fill up a full heart container. If a Rotten Heart is picked up at full health, it will replace the rightmost red heart.

For each Rotten Heart possessed upon clearing a room, two blue flies will spawn. You cannot have half a Rotten Heart; they are always depleted in one hit.

Depleting a Rotten Heart will not count against Devil Deal Chance when it's the rightmost red heart.

Rotten Hearts are unlocked by entering the Corpse for the first time.


  • Although a Rotten Heart is depleted in one hit, under certain circumstances you can have half a rotten heart. After you start taking a full heart damage from enemies, if you get damaged with a Rotten Heart next to half a red heart, the rotten heart will be damaged to half, instead of being destroyed fully.
    • A half Rotten Heart looks identically to a half Red Heart, but it also spawns two blue flies. Grabbing half of a regular red heart will "repair" it. Taking half-a-heart damage will deduct half a heart of Isaac's health, however, taking full-heart damage will deduct 1.5 red hearts.


Three new pill effects were introduced in Antibirth.

Pill Effect
Experimental Pill

Increases one random attribute and decreases a different random attribute. Will not decrease attributes with PHD.

Shot Speed Down

Decreases shot speed.

Shot Speed Up

Increases shot speed.


  • It is possible for an Experimental Pill to decrease health while Isaac has one heart container, killing him.


Multiple new runes were added to Antibirth. When on the ground, these runes look like: Rune3.png

Rune ID Icon Message Unlocked by completing Effect
Rune of Gebo 60 Gebo Icon.png "Charity" 4x. Bloody Mary Donates to a machine or beggar
Rune of Kenaz 61 Kenaz Icon.png "Pestilence" 2x. Scat Man Poisons all enemies in the room
Rune of Fehu 62 Fehu Icon.png "Wealth" 3x. Turbo Turns all the pickups in the room into coins
Rune of Othala 63 Othala Icon.png "Legacy" 9x. Seeing Double Rewards a random item that Isaac already holds
Rune of Ingwaz 64 "Treasure"
Rune of Sowilo 65 "Renewal"

Sacdag.png Antibirth Sacdag.png

Boss Baby Plum.png Bosses MainPageChallenges.png Challenges MainPageChapters.png Chapters Character.png Characters Book of Virtues.png Items
Dumpling.png Monsters Bucket.png Objects Immortal Heart.png Pickups Blessed Penny Icon.png Trinkets MainPageAchievements.png Unlockables