Super Namek
From Multiversal Omnipedia
A Super Namek is apparently the Namekian equivalent of a Super Saiyan, Namekians possessed of unusually high levels of power. Piccolo became a Super Namek after his fusion with Kami.
Movies
Piccolo wasn't the only Super Namek, as explained by King Kai. Long ago, before the destructive storms hit Planet Namek, there was a tribe of ancient Nameks that have reached a higher power level. They soon intoxicated by their power and began to misuse it. The good people of Namek used the Dragon Balls to banish them away from the planet forever. Lord Slug was the last one.
