I’m currently working on a Unity Domain cleric build, and I believe the wording of the ability Shared Burden is intended to be different than the RAW wording.
When a creature you can see within 30 feet of you takes damage, you can use your reaction to choose a number of other willing creatures you can see, up to a number of creatures equal to your Wisdom modifier (minimum of one creature). Distribute the damage taken between the original target and the chosen creatures. Each creature must take at least 1 damage. Apply any damage resistance or vulnerability of the creatures involved after you distribute the damage.
It says a creature you can see within 30 feet of you. It doesn’t specify "another creature", so based on my interpretation you can use this on yourself.
Is my interpretation correct? Can a Unity Domain cleric use Channel Divinity: Shared Burden as a reaction when the cleric takes damage?