Gwendolyn "Gwen" Tennyson, is Ben's first paternal cousin. She is in Ben's Team and has been helping Ben since he found Omnitrix. Gwen is 1/4 anodite and 3/4 human revealed in What are little girls made of? by their grandma Verdona. She can conduct mana (life energy / sometimes magic) and recite spells. With this ability she is able to defeat bad villans.
Gwen Tennyson