Birch’s Bloody Thorns

Thorny Rose vines wrap around your arms and dig into your flesh, cutting you badly. You take 5d8 necrotic damage, which cannot be reduced in any way and up to 6 creatures regain hit points =damage taken +proficiency bonus. After its initial casting, you can concentrate on the spell to do additional healing equal to your spell-casting ability modifier. 

While concentrating, the caster in in excruciating pain and cannot be healed. 
At Higher Levels

When you cast this spell slot of 5th level or higher, the necrotic damage taken increases by 2d8

if this spell is cast with a slot of 6th level or higher, the necrotic damage is maximised.