There is a boon from Hestia (I don't remember the name of it off the top of my head) that grants bonus damage every time you gain a Centaur Heart or Centaur Soul. The boon itself gives a Centaur Soul but the boon doesn't say anything about it. This should be added into the boon description when you pick it up (like how the corresponding one does from Dionysus with Nectar and bonus health).
There is a boon from Hestia (I don't remember the name of it off the top of my head) that grants bonus damage every time you gain a Centaur Heart or Centaur Soul. The boon itself gives a Centaur Soul but the boon doesn't say anything about it. This should be added into the boon description when you pick it up (like how the corresponding one does from Dionysus with Nectar and bonus health).
Edit to add: The boon name is Melting Heart.