Mom's Locket

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

Effects

 * Grants half a red heart each time a key is used to unlock a door, golden chest, or key block.
 * Turns half red heart pickups into full hearts. Half hearts already on the ground will also be upgraded upon re-entering the room.

Synergies

 * Humbling Bundle cannot alter half red hearts, but Mom's Locket turns half red hearts into full red hearts, which it can double.