Mom's Locket

This article is about Mom's Locket, similar in appearance to Friendship Necklace.

Mom's Locket is a trinket added in The Binding of Isaac: Afterbirth.

Effects[ | ]

Grants a Half Red Heart each time a Key is used to unlock a door, Locked Chest, or key block.
Turns Half Red Heart pickups into Red Hearts. Half hearts already on the ground will also be upgraded upon re-entering the room.

Having Mom's Locket while playing Keeper or Tainted Keeper will restore a full health coin when a key is used.
Donating keys to a Key Master won't heal Isaac.
A very useful trinket for unlocking the It's the Key achievement, in which Isaac cannot pick up coins, bombs, and most importantly, hearts.
Tainted Bethany is granted a blood charge upon using a key.

Equality!: As long as Equality is active, all red hearts will be double.
Humbleing Bundle: Humbleing Bundle cannot alter half red hearts, but Mom's Locket turns them into full red hearts, which it can double.
Hypercoagulation/Soul of Magdalene/ Tainted Magdalene: Created temporary half hearts are now full red hearts.
Birthright+ Tainted Eve: Blood clots drop full hearts rather than half hearts, making it possible to infinitely make two for one.
The Jar: Any half red hearts stored by The Jar will be converted to full hearts when dropped on the ground. Since The Jar will store any leftover health from healing Red Heart Containers, this can allow for potentially infinite health when healing half-empty containers. Especially effective in conjunction with Cancer or The Wafer.

Golden Key/Pay To Play/Paper Clip: Renders Mom's Locket less effective as the trinket requires a key to be consumed by the lock in order to heal Isaac.