Seth
Seth spent many centuries disguising himself as a cult leader and when all hell broke loose, he managed to �disappear� and start another cult.  Seth's first appearance was in the episode Seth [hence the title].  The SGC tried to stop Seth from creating more of these cults by invading his new HQ(Head Quarters).    He was killed when Samantha Carter tried on the Hand Ribbon Device and aimed it towards him.  He was also in the episode the Gamekeeper.  He is superbly played by Robert Duncan. 

Mythology of Seth
The god Seth and Mehen were often depicted defending the solar barque and...

A Picture of Seth