Ultimate Swampfire

Ultimate Swampfire is the ultimate form of Swampfire. His first appearance was in The Final Battle: Part 2, making it Ben's first ultimate transformation, a reference to Ben's transformation to regular Swampfire in Ben 10: Alien Force, being his first transformation when puts on the Ultimatrix. He will appear in Ultimate Alien, as one of Ben's new aliens. He is voiced by Dee Bradley Baker.

Appearance
After the induced evolution, Swampfire now appears as humanoid tree with three blue gooey shells containing an organic, blue-colored kerosene gel-like solution, (as said by Dwayne McDuffie) that Ultimate Swampfire shoots out and ignites, creating more intense, blue-colored flames. He is the same size as original Swampfire. He has many of the same abilities. He also has the same feet as Swampfire. He now has a blue Heatblast-like face inside a blue bubble.

Abilities
His pyrokinetic and chlorokinetic abilities are greatly increased, and he can still regenerate body parts. His speed is also the same as his original form but he makes up for it with his lethal fire bombs that have knocked even Vilgax out cold. Ultimate Swampfire shoots blue flames while Swampfire shoots ordinary-colored fire. He also shoots a huge pyrokinetic beam when he combines his hands together.

Trivia

 * Ultimate Swampfire is the first alien Ben used as "Ultimate", reflecting on how Swampfire was the first alien Ben used in Alien Force.
 * He is the alien in an online Ben 10 3D game called Ultimate Crisis
 * In a beta Ben 10 action comic cover Ultimate Swampfire appeared to resemble Heatblast, being red, while the kerosene shells were yellow.

Hero Form

 * Swampfire