Dark Chronos

Dark Chronos (real name: Lucas Saunders) is a high tier GMod Monster and is one of the notable three masters of time manipulation along with Lyktgubba and The Visualizer.

He, along with his subordinates collectively called the Chaos Force come from an alternative timeline in the TF2 Freak Universe where he and his subordinates suffer pain in their life from the Freak Breakout Incident.

He and the Chaos Force plan to reverse that by eliminating every Freak from the past in order to prevent the killing of his family.

Backstory
In the alternative timeline, after the Freak Breakout Incident his family are killed. This leads to his current motivation on killing past Freaks in order to turn the tides of time.

To follow his cause, he brought up soon-to-be members of the Chaos Force and soon unraveled his own powerful abilities.

Trivia

 * It is hinted from his behaviour that he is somehow related to Arion or is an Alternative Future version of him.