I have concerns about the immense healing potential that the Healing Spirit spell can put out.
As it appears in Xanathar's Guide to Everything (page 157), the Healing Spirit spell is able to heal any creature that starts its turn within its effect, or passes through it during their turn. In practice, this spell is limited by the mobility of the party that tries to take advantage of it, but in my experience, the spell is still able to dramatically improve the hitpoint recovery of the whole party, along with minimizing the impact of Unconsciousness or Death Saving Throws. In my experience, campaigns where Healing Spirit is accessible tend to trivialize/obsolete use of features like Hit Dice, Second Wind,
For reference, at its base level, it's capable of healing any creature that runs through it for 1d6 hit points once per turn for 10 turns. So even if you only hit a single creature, you're still confidently healing an average of 35 hitpoints to a single creature, and much more than that on more than one creature. And all of that scales with the level of the spell. The spell, once cast as a Third Level Spell, is strictly better than the Paladin-exclusive spell Aura of Vitality (also a third level spell), which has action-economy restrictions and does not scale with level, and unlike Aura of Vitality, Healing Spirit is accessible to a full-spellcaster capable of upcasting the spell and casting the spell many more times in a day.
It's also been my experience that banning "out of combat" use of the spell doesn't help much, since it only takes a single combat encounter being dragged out to permit optimal use of this spell.
I could choose to ban the spell entirely, but I want to consider a compromise first before I resort to that. So for my campaigns, I'm proposing the following version of the spell designed to keep some of its power as a healing spell while tempering its more ludicrous features:
Casting Time: 1 bonus action
Range: 60 feet
Components: V, S
Duration: Concentration, up to 1 minute
You call forth a nature spirit to soothe the wounded. The intangible spirit appears in a space that is a 5-foot cube you can see within range. The spirit looks like a transparent beast or fey (your choice).
Until the spell ends, whenever you or a creature you can see moves into the spirit's space for the first time on a turn or starts its turn there, you may use your reaction to cause the spirit to restore 1d6 hit points to that creature. The spirit can't heal constructs or undead.
As a bonus action on your turn, you can move the spirit up to 30 feet to a space you can see.
The two changes are the following:
- Instead of being a free action, healing with this feature now requires the use of the spellcaster's Reaction
- The ability to gain benefits by upcasting the spell have been removed
So in general, this is a significant nerf to the spell. It becomes unable to be upcast, and it can only heal one creature per turn. It puts the spell more in line with the relative power of spells like Aura of Vitality while still making it accessible very early for low level druids. I think the spell will still be competitive in terms of raw healing output and for helping keep allies alive, while keeping it from trivializing all other possible sources of healing.
Does this version of the spell bring it more in line with the relative power level of other sources of Healing? Or are my assumptions/observations about the power of the original spell off-base?