FrogReaver
As long as i get to be the frog
I would argue this is the primary reason to ban anything in the game. The vast majority of OP things do something more efficiently than other options.
Remember that 5e challenge is not based on an encounter...it’s based on a string of 5-6 encounters. This is especially true at higher levels where a party can handle “deadly” encounters with ease until they have been drained of some resources.
So anything that replenishes resources easily can be quite powerful...it’s not as obvious as something cast in combat.
Though speaking of combat. If a player is knocked out on the spirits space. At the start of their turn they get the healing...does that mean they get their turn?
If so, thst is an incredible combat advantage. It’s like regeneration but 4 levels lower
I've yet to see healer feat, prayer of healing, leominds tiny hit or almost any other spell that allows you to get resources back break the game.