Anathema

You cast this spell as a reaction to a friendly creature within the spell's range to taking damage from an attack or effect created by another creature, which becomes the spell's target. When you cast this spell, the target becomes wrought by radiant chains, in response to the audacity one must bear to harm your precious allies. While the target is wrought by these chains, it receives the following effects:

Bound: While the creature is bound by radiant chains, it finds itself harder to move as the chains constrict its movement. A creature affected by this spell has its AC reduced by 2, its dexterity score reduced by 3, and its movement speed reduced by 10 ft.

Branded: While a creature is bound by radiant chains, it finds the chains searing it as it moves. Whenever a creature affected by this spell moves at least half of its movement speed, it takes 1d6 radiant damage. A creature also takes this damage whenever it makes an attack, or is hit by another creature's attack. A creature can only be affected by each of these sources once per turn, resetting at the start of its turn (for a total of 3d6 radiant damage in a single round).

Broken: When a creature bound by radiant chains is destroyed, so too are its chains. When a creature affected by this spell is reduced to 0 hit points, the chains on it shatter. Any creatures within a 10 ft. radius of the target either take 3d6 radiant damage, or heal for 3d6 hit points, of the caster's choice.