Bleeding Strike (5e Spell)
From D&D Wiki
|Casting time:||1 reaction, which you take in response to being damaged by a melee weapon attack|
|Duration:||Concentration, up to 1 minute|
When another creature strikes you with a melee weapon attack, you use your reaction to cast this spell. Your blood lunges towards that creature, and deals 2d6 piercing damage, then latches on. For the duration, the creature must make a Constitution saving throw at the start of each of its turns. On a success, the spell ends. On a failure, the creature takes 2d6 necrotic damage.
At Higher Levels. When you cast this spell using a spell slot of 4th or higher, increase the piercing damage by 1d6 for every spell slot level above 3rd.