"Guardian"

"Guardian" was a Dark Hunter whose job was to track down captured Hunters and ensure they didn't betray the Hunters by revealing secrets.

History
"Guardian" came from a war-torn island, and when a friend betrayed his tribe to their enemies, he was caught in a crossfire of Rhotuka Spinners and left for death. The Dark Hunters saw him as useful and nursed him back to health.

He served the Dark Hunters for years, presumably, tracking down and assassinating captured Dark Hunters. Eventually in 1001 AGC, Teridax took over the universe and Guardian found himself in the rebellion force, a rebellion in which he was killed.

He was in Karzahni at the time of his death, in a team consisting of himself, Tahu, Kopeke, Johmak, Krahka, and Lariska. Guardian began to have his doubts about Tahu's plan to "smash everything and hope to be somewhere else when it all goes boom" and decided to go out on his own and see if he could find a way out of the universe. However, as he did so, Teridax decided to personally kill Guardian, having the earth open and swallow him whole, crushing him.

Dark Mirror
In the Toa Empire Alternate Universe, "Guardian" is one of three Dark Hunters that are part of a resistance group attempting to eliminate Toa Tuyet. During the battle, "Guardian" teamed up with Nuju to fight a Toa of Magnetism. He later died during the battle, but managed to take six other Toa with him.

Powers and tools
Guardian had sharp claws and a Staff that could launch earth related Rhotuka Spinners.