Way Big

Way Big is a To'kustar (perhaps a play on the "tokusatsu" superhero genre in Japan, given Way Big's appearance being similar to Ultraman). He is the biggest alien in Ben's arsenal. Way Big's extraordinary size of over 100 feet grants him extraordinary strength and invulnerability to most attacks. Way Big is used as Ben's "big gun" like Fourarms and Humongousaur but sometimes fails to use him as the Omnitrix (and now Ultimatrix) decides which alien to change. He is also in Ben 10: Ultimate Alien.

Abilities
Due to his enormous size, Way Big can easily overpower most of his opponents. His size also grants him incredible strength. He has also shown great durability, withstanding fire from enemies while barely even feeling them. In addition, he is also incredibly strong for his size, as demonstrated in Primus, when Vilgax became gigantic after absorbing the codon stream. Although he was approximately the same size as Way Big, Ben was easily capable of lifting Vilgax, and throwing him through a wall, and outside of the planet's atmosphere.

Original series
Way Big first appears in Ben 10: Secret of the Omnitrix, when Azmuth activates it on the Omnitrix so Ben can fight off Vilgax's army. His only appearance in the TV series itself was in Ken 10 when Ben loses his temper and viciously beats Kevin into the ground after he pushes him too far by injuring Kennny (just the impacts of his blows was enough to wipe out the section of the city they were fighting in). This makes Way Big justifiably one of Ben's ultimate weapons. As soon as this form comes out, he can make short work of Vilgax and Kevin 11,000, something no other form has come close to doing, the only exception being when in Vilgax Attacks, Ben is aboard Vilgax's ship and Ben makes short work of Vilgax, his ship, Psyphon, and Vilgax's army as Alien X.

Alien Force
Way Big, Upchuck, and Cannonbolt are in the season 2 finale of Ben 10: Alien Force after Azmuth unlocks the Omnitrix's Master Control. His eyes are now green instead of yellow, the spikes on his shoulders are gone, his face is different and the fins on his hips are gone. This is possibly due to the fact that the aliens age as Ben does, and possibly that To'kustar's become more streamlined with age. This however contradicts the episode, Ken 10 from the original series, in which Way Big still looked the same as he did in Secret of the Omnitrix, despite Ben being an adult now. Way Big is also the only alien that is bigger than Humongousaur. Lately, since the incident in which Way Big "escaped" from the Omnitrix, whenever Ben tries to transform into him, he ends up switching into another form such as in Vengeance of Vilgax: Part 2, when he tries to become Way Big and instead becomes Chromastone,and in If All Else Fails where he accidently transforms into Humongousaur instead of Way Big(although Humongousaur is one of the biggest aliens as well, but the monster he was going to use Way Big to fight was smaller than Way Big and Humongousaur can only grow to the size of its foot), and in In Charm's Way where he tries to go Way Big and becomes Bengax (although he thought the Bengax hologram was the Humongousaur hologram and any alien could defeat Undead Fighters). Way Big makes another appearance in Simple to stop a war from another planet. Way Big appeared in Primus as well. He is now Ben's permanent additional alien.

Ultimate Alien
Way Big briefly appeared in Video Games, crushing Harangue's robot and his car at nearly the end of the episode with his same appearance in Alien Force.

Original series

 * Ken 10 (used by Ben 10,000)
 * Ben 10: Secret of The Omnitrix

Alien Force

 * War of the Worlds: Part 1
 * Simple
 * Primus

Ultimate Alien

 * Video Games

Trivia

 * Way Big defeated Vilgax in Ben 10: Secret of the Omnitrix, and defeated him again in Primus.
 * To'kustar's don't have a home planet. They are Unborn during astronomical storms And Arcsrimedas.
 * He is one of 5 aliens to appear in all three series. The other 4 are Cannonbolt, Upchuck, Ghostfreak and Diamondhead.
 * He is the 3rd alien from the original series to reappear in a sequel series.
 * Since Secret of The Omnitrix is based as the last cartoon episode, Way Big is the last cartoon alien used in the original series.
 * Way Big and Alien X both are the strongest aliens in the Omnitrix and Ultimatrix.