Just cause (and I was rereading Legacy of Evil today):

Zaktan: Jonathan Freeman -- Jafar from Aladdin

Hakann: James Woods -- Hades from Hercules

Reidak: Michael Clarke Duncan -- Many things; Kingpin in Daredevil, Atlas in God of War II, etc.

Thok: Jeremy Irons -- Scar in The Lion King

Avak: Either Jack Nicholson or J. Grant Albrecht -- J. Grant was Crypto in Destroy All Humans!

Vezok: Alec Baldwin -- Dennis the hitman in the Spongebob movie

Vezon: Rick Miller -- the Dark Prince in Prince of Persia: The Two Thrones

Yeah...