If the character cannot hold red heart containers they will simply be given a normal HP up.
Adds a chance of dropping a Red Heart after taking damage.
Notes
The chance for Old Bandage to spawn a Red Heart depends on the luck stat, and the formula used to determine the chance is:
At base luck (0), the chance is 10%, maxing out at 50% at 26.67 luck.
The chance for Old Bandage to spawn a Red Heart depends on the luck stat and is based on this formula:
This means that the chance starts at 20% at 0 luck, minimizes at 0% at -20 luck, and maximizes at 100% at 80 luck.
Synergies
Blood Oath: For each half heart damaged by Blood Oath, Old Bandage has a chance to drop a heart. Synergy further improves with luck.
IV Bag + Humbleing Bundle / Maggy's Bow: The damage from IV Bag has a chance to spawn 2 hearts, which can be picked up to create further coins and possibly even heal hearts with enough Luck.
Humbleing Bundle only has a 50% chance to double the hearts dropped, but Old Bandage may still drop 1 heart.