Regeneration

Regeneration is the mastery spell of the Emerald bloodline. An advanced version of healing, regeneration can heal even fatal damage so long as it is done quickly enough, and the damage is not instantly fatal or irreparable such as destroying the heart or severing the brain stem. Otherwise Regeneration can effectively heal any injury if performed properly. It uses the sorcerers own magical energy or Mana to create new organic tissues and heal major damage in a matter of seconds. Its been shown that a regeneration spell can even repair a large hole pierced through someone's lungs almost instantly where as normal healing would likely work too slow and the subject would die before the damage could be repaired enough to stabilize them. It is this ability that makes a master emerald so powerful and resilient as they can potentially recover from any injury with ease so long as they have the Mana pool to cast the spell. 
Emerald Regeneration can also be used to slowly grow a fully natural and living body from a tissue sample like a kind of Arcane Cloning, but the body created would be a mindless and soulless shell and would need to have a Soul placed into it with Diamond Magic. This process can take months however as it requires a lot of focus and effort. There are also certain Emeralds who are able to help other Sorcerers regenerate from major injuries such as growing back severed body parts, but this process is described as extremely painful and long depending on the size of the body part in question with a single hand being said to take about three days to regrow where as several limbs would take up to six weeks.