Healing with heart wisps
What changes
Kills made by these wisps' tears can drop a full red heart. The drop is a chance, rather than a reward for every kill.
How to approach the setup
Keep Yum Heart as the active item combined with the book. Use a ready charge when healing is useful, then give the surviving wisps firing lanes while you dodge.
A practical suggestion for this pair. Check the rest of your inventory and the room before relying on it.
The caution to remember
The wisps do not create guaranteed healing on demand. Red-heart recovery also needs a character who can use red hearts; check your health type before relying on it.
What this teaches about a run
A healing active can also support combat. Treat an occasional heart drop as a bonus rather than a reason to spend health recklessly.
Other reviewed pairings
Book of Virtues + Shoop da Whoop!Shoop da Whoop! creates wisps that fire thin lasers when you use the active, instead of shooting ordinary tears.Book of Virtues + Prayer CardPrayer Card creates white heart-shaped wisps whose tears behave like Sacred Heart tears.Book of Virtues + Unicorn StumpUnicorn Stump creates rainbow wisps that can deal contact damage while Isaac is invulnerable.