Monday, February 4, 2013
David Kim was a Korean-American scientist that created nanotechnology capable of regenerating tissues. A villain named Dr. Sugarman (no relation to the X-Men villain Sugar Man) wounded David. His assistant used the nanities to turn David into an immortal "xombi". Because he is immortal, he found himself caught in the affairs of ancient supernatural creatures.
After the multiverse was destroyed and fixed, we see two versions of Kim. One (from another timeline) became Green Lantern. Another one (in the main DC Universe) was basically the original version of Xombie and allied himself with the Spectre to fight a life force-sucking ghost. DC Comics announced a new Xombi series.
The nanotechnology regenerate his body and prevents aging and illness. He can heal almost instantly from any attack. This make him virtually immortal. He can also transmute certain substances via the nanotechology.