Gregor is a clone commando introduced in the fifth-season Clone Wars episode "Missing in Action" (2013), voiced by Dee Bradley Baker. Presumed killed in action, he is found working in a diner on the Outer Rim world Abafar with no memory of who he is.
The episode is a small, strange piece of work about a soldier recovering an identity he might have been better off without. He returns in Star Wars Rebels as one of the three veterans on Seelos and in The Bad Batch, where he is one of the clones held at Mount Tantiss.
Catalogue entry. This figure has a verified record here rather than a full write-up — the encyclopedia labels its own depth instead of padding it.