Regenerate Spell
D&D Description of the Regenerate Spell : The subject's severed body members (fingers, toes, hands, feet, arms, legs, tails, or even heads of multiheaded creatures), broken bones, and ruined organs grow back. After the spell is cast, the physical regeneration is complete in 1 round if the severed members are present and touching the creature. It takes 2d10 rounds otherwise.
Deeper info on this Dungeons & Dragons Regenerate Spell