Rukh is a Noghri assassin and bodyguard from Honoghr who serves Grand Admiral Thrawn. He was created by Timothy Zahn for Heir to the Empire (1991), where the Noghri serve the Empire because it deceived them into believing it was repairing an ecological catastrophe it had caused — and where Rukh, on learning the truth, kills Thrawn himself at the Battle of Bilbringi.
Current canon reintroduced him in Star Wars Rebels season four ("Kindred", 2018) as Thrawn's tracker on Lothal, hunting the Spectres by scent and capturing Hera Syndulla. He dies in the liberation of Lothal, caught in the Imperial Complex's shield generator with his foot trapped in the wiring, electrocuted when Kallus raises the shield. Zahn has suggested the two may not be the same individual, since Rukh could be a common Noghri name — which is a tidy way of preserving both endings.
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.