Looking for the name of a lesser known Star Wars character, can you help?

I think he's come out briefly in Return of the Jedi, in Jabba's palace. I'll try to describe him as best I can. Not sure how tall he is but he's one ugly mother! He seems to be an assasin of some sort, yellow/greenish in color has HUGE hands and tiny small red eyes.

He carries a walking stick with the skulls of a few victims and with the other hand he drags around the corps of another victim. Super creepy. I think his name starts with an "A". Thanks!