Lazarus 92 is the main antagonist of Episode XCIX of Season 5 in the Samurai Jack series. He is one of the most dangerous criminals in the whole universe. It is a being made from multiple blue leech-like creatures.
Lazarus 92 was a homicidal collective consciousness with only one thing on its mind: killing, probably the reason it was incarcerated in the first place. It's figurative lack of a conscience was implied after its transport vessel crashed on Earth, where it escaped and indiscriminately killed the ship's crew and its fellow inmates in a seemingly short span of time.
Despite its brutality, it was not smart or clever enough to search for a way off the ship, preferring instead to hunt Jack and Ashi, not knowing this would be its undoing.
Little is known about Lazarus 92's history, but it is a criminal who was captured by the authorities. Unfortunately, a large asteroid hit the spacecraft it was being transported on, causing the ship to crash-land on Earth.
The creature escaped after, killing the other prisoners and crew members alike.
Ashi and Samurai Jack soon encounter Lazarus-92, but Jack is unable to figure out the initiation sequence. Jack and Ashi fight on, but are soon surrounded. Jack tries once more to activate the weapon while Ashi covers him, the weapon activates and electrocutes the Lazarus.
As the creatures die, the infection in Jack and Ashi's wounds is also neutralized.
- Lazarus-92's fate after Jack destroyed Aku in the past is unknown, given the fact that unlike other antagonists, Aku most likely had no influence over it and was already a deranged criminal in his timeline, aside that we don't know if Aku ordered its capture or its imprisonment. Therefore, it's presumed, in case that Aku had some influence over it, that in the current timeline Lazarus-92 remains imprisoned (if it ever came to exist) or that alternatively, as Jack and Ashi were never there, Lazarus-92 was able to leave its transport and caused havoc on Earth.