Wizards: Wizards came from overseas around 1000 TA to help Free Peoples of Middle-earth to suppress Evil. Wizards do not rule over living-beings. They help men, elves, dwarves, and hobbits and eagerly share their wisdom with them. Wizards can solve even the most difficult riddles.
Iluvatar himself ordered one of the istari to head White Powers and fight for the Ring. If you happen to win it, then your mission will end successfully.