Agen Kolar is a Zabrak Jedi Master, introduced in Attack of the Clones (2002) and played by Tux Akindoyeni. He survives Geonosis, joins the High Council for Revenge of the Sith, and is written throughout as a blade rather than a diplomat.
He is remembered for four seconds of film: standing behind Mace Windu when Palpatine drops the act, and being cut down before he can raise his guard. The scene needed a Jedi Master to die instantly and without dignity to establish the stakes, and Kolar is who it used.
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.