Cin Drallig is a human Jedi Master from Lavisar and the Jedi Temple's battlemaster — the Master responsible for lightsaber instruction. He appears in Revenge of the Sith (2005), played by Nick Gillard, the trilogy's own stunt coordinator and swordmaster, which is a joke with a point: the man who choreographed every duel in the prequels plays the man who taught everyone to duel.
He is on screen for seconds, defending the Temple against Anakin Skywalker during Operation Knightfall and losing. The Legends material around him — games, guides, comics — made him the teacher of most of the Order's notable blades. It is a small, elegant piece of worldbuilding: the Purge did not just kill Jedi, it killed the person who knew how the Jedi fought.
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.