Gwen Tennyson (Classic)

Gwendolyn "Gwen" Tennyson is Ben Tennyson's cousin (the two share the same birthday). Throughout the original series, she constantly bickers and insults him with dry wit and sarcasm. Gwen was first introduced in "And Then There Were 10". She uses her laptop to research any strange people and/or creatures they might come across.

Synopsis
In the sequel series, Ben 10: Alien Force, Gwen (voiced by Ashley Johnson) has grown into a calm and collective teenager. In this version, Gwen wears a plain, white shirt, loosely-buttoned blue sweater, a black skirt with black tights, her hair is much longer and darker, her eyes are much darker, and her lips are more visible. Gwen, despite now being a black belt, tends to favor her magical powers over her martial art skills. She is able to create energy constructs for nearly any purpose, usually creating platforms to levitate herself (and others), beams to grab enemies, circular blasts to knock enemies back, projecting beams from her eyes that seem to simulate heat vision, and opening up inter-dimensional portals. She also has a wide range of other loosely defined magical abilities, such as dowsing, limited telepathy, and clairvoyance. Her powers are revealed to be alien in origin; her grandmother, Verdona, is an energy being alien.

Energy Manipulation


Given her Anodite lineage, Gwen is capable of energy manipulation. She also has a wide range of other loosely defined magical abilities, such as dowsing, telepathy and clairvoyance.

Her powers are revealed to be alien in origin; her grandmother, Verdona, is an energy being known as an Anodite. Verdona tells Gwen that what she and others originally thought of as "magic" was actually the manipulation of a Force-like energy called mana. Verdona offers to take Gwen to her home planet and train her in the mystical ways of the Anodites, but Gwen prefers to remain on Earth with Ben and Kevin. She hates being called an "Energy being", referring to her Anodite heritage. In 'War of The Worlds', Gwen releases her Anodite form, and was almost overwhelmed by her own power before Kevin snaps her out of it. Gwen can also conjure up dimensional vortexes.

"Magic"


In the original series, Gwen's powers first manifested in the form of what she originally believed to be "magic", thus enabling her to use various magical artifacts and spells (see Gwen's Spells). When using the magical, luck-giving Charm of Bezel, she was able to activate it instinctively, whereas Hex did or could not. Later on, when she takes and uses his staff, she was able to make it fire an energy blast—according to Charmcaster, only someone of Hex's skill should have that power. Gwen starts tapping into her magical powers when she procures a book of spells from Charmcaster in the episode "A Change of Face".

On two occasions, Gwen used the Charms of Bezel to become a superheroine by the name of Lucky Girl. At first, her ability drew from the "luck" Charm of Bezel, which innately gave her perfect luck. While wearing the charm, any action she took would result in an Rube Goldberg-style chain reaction benefiting her original intent, but usually injuring Ben in the process. She later brought back her superhero identity after obtaining the Keystone of Bezel, which increased her natural abilities to superhuman levels rather than just affecting her luck. Both times, Gwen was forced to retire when the Charms of Bezel were destroyed.

In Alien Force, despite Gwen's current preference for direct forms of mana manipulation, she is still able to use "magic" in the more traditional sense. Gwen mentions to both Charmcaster and Kevin in In Charm's Way that she still has Charmcaster's old spellbook, and is currently looking through it constantly to find a cure for Kevin's mutation.

Athletics
Gwen is a capable gymnast and has had some training in martial arts. At the age of fifteen it is revealed that she has already received a black belt in karate and has even started teaching Ben.

Intelligence
Gwen is shown to be quite intelligent and knowlegdeable (if more so than Ben). Before discovering her powers she would often use her "brains" to help Ben. She is shown to be a bit of computer/tech wiz as well.

Trivia

 * In the original series, Gwen is voiced by Meagan Smith.
 * In Ben 10: Alien Force, Gwen is voiced by Ashley Johnson.
 * In the episodes "Ben 10,000" and "Ken 10", Gwen is voiced by Tara Strong. Incidentally, Strong also voices the 10-year-old Ben.
 * In the live-action movie, Ben 10: Race Against Time, Gwen was played by Haley Ramm.
 * Gwen's magical abilities and even her name might have been inspired by the Sibyls from Chris 'D Lacey's series of books,The Last Dragon Chronicles. In the series, Sibyls are able to command the supernatural, and they are the descendants of a powerful magics user, Gwendolen.
 * Gwen`s lucky girl suit looks simlar to Hellcat from Marvel.
 * The Cat logo on Gwen in the first series looks very similar to Sly Cooper's logo.