Wyrd Reconstruction

You call upon the unstable magic of otherworldly powers to reshape the body of a creature you can see within range. The target regains hit points equal to 2d12 + your spellcasting ability modifier. At the end of the healing process, the creature takes 1d6 necrotic damage, and must make a constitution saving throw (DC 10 + Spell Level) as their flesh is reconstructed. On a failed save, the creature takes 2d4 additional necrotic damage. On a critical failiure, the damage increases to 4d4. On a critical success, their newly mended body grants the creature a +1 bonus to their AC until their next long rest. 

Damage from this spell can not be reduced in any way. If the creature takes damage from this spell that would reduce it to 0 hit points, it is reduced to 1 hit point instead.

A creature can only be targeted by this spell a number of times equal to their constitution modifier + 1 per long rest. This spell has no effect on constructs.

At Higher Levels. When you cast this spell with a spell slot of 3rd level or higher, the healing recieved is increased by 1d12, the damage taken on a failed save is increased by 1d4, and the damage on a critical fail increases by 2d4 for every spell level above 2nd.