Gwendolyn "Gwen" Tennyson is Ben 10's cousin and one of Society's scout,
She is a Human/Anodite hybrid Plumber, the paternal first-cousin of Ben Tennyson, and (along with Kevin Levin) a frontline member of his team. Gwen was first introduced when her parents send her on a summer-long road trip with her Grandpa Max and her cousin Ben. She has, as Verdona refers to it, "The Spark".
Her magical powers and abilities have greatly strengthened and increased to even higher power levels, and she is easily able to control and manipulate pure pink glowing energy from her magical aura to create energy blasts, shields, barriers, and other structures, like hammers, protective helmets, battering rams, beams to grab and hurl enemies, stepping stones to carry herself and others through the air, and safety nets; turns out that Gwen can also synchronize her martial arts styles with her mana manipulating abilities. It is also revealed that her paternal grandmother Verdona was an energy being known as an Anodite from the distant planet Anodyne, a free-spirited alien species who possess the exceedingly strong and powerful power and ability to manipulate and control a supernatural force-like substance called life energy most commonly known as mana (which can also be referred to either chakra or chi), the very source of magic itself, which explained Gwen's unusual affinity with magic. Gwen is also able to take on an Anodite energy form like her grandmother if she is under a great deal of stress. Also notable is that over the course of the later series, she has two character designs. Her blue dress was featured in the first two seasons of Ben 10: Alien Force, and then a later red-coloured redesign appearing in Ben 10: Alien Swarm when the gang goes to Missouri, later used in the third season of Ben 10: Alien Force, and recycled later on Ben 10: Ultimate Alien.
Gwen is shown to be very intelligent and knowledgeable. Before discovering her dormant innate magical and Anodite powers, she would often use her "brains" to help Ben. She is shown to be a bit of computer and tech wiz as well. She has her own laptop which she uses to research enemies she meets. She is straightforward and very brave despite the circumstances. Gwen is a very well student, especially in episode "It's Not Easy Being Gwen", where shows that Gwen takes her education very seriously. Showing to come home late at all hours of the morning and having to wake up at 5:30am, when waking up so early she does a number of things before going to school. Such as jogging, practice French, school, and afterschool karate classes. It’s also presumed that Gwen goes to private school since it shown that her usual clothing is actually a uniform at her school.
Appearence in UltimaEditShe and her cousin were somehow caught the energy wave that caused to revert back to their 10 year old body, since then, they been helping the Society in battle and on scouting for refugee.
then another wave strike again when they somehow trying to open a portal back to HQ, revert back again to her current age again even her power is still the same