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Gwen Tennyson is the paternal cousin of Ben Tennyson. She helps out Ben in the fights, often being the brain to Ben's brawn. In the Prime Timeline of the Classic Continuity, she learns magic and discovers latent powers related to mana manipulation. While in the Main Timeline of the Reboot Continuity, she is depicted as a normal human girl. She is one of the main characters in the Ben 10 franchise.