Users possess extreme regeneration, allowing them to not only recover from any wound almost instantly, but even regenerate separated body parts into full bodies, each as powerful as the original. This tremendous life-force is usually associated with some kind of biological immortality, all bodies being connected together in a unique hive mind.
Pernida Parkngjas (Bleach) growing additional copies of itself out of severed fingers.
Aoba Takatsu's subordinates (Code:Breaker) possess the ability Cell Stimulation, which causes their cells to grow and regenerate whenever they are attacked, even creating clones when severed.
Infinite Zamasu's (Dragon Ball Super manga) regeneration is so powerful that he was able to survive being blasted to pieces and had pieces regenerate to form clones of Fused Zamasu.
Utsuro (Gintama) regenerated an entire body from his severed right arm alone, leaving his former body as a decoy clone to distract Umibozu; doing so, however, greatly drained him of his Altana, which can only be recovered if on Earth.
Elg (Toriko) regenerated each shard into a full body after being shattered into a thousand pieces by Buranchi's lightning sword technique.