Ultimate Swampfire

Ultimate Swampfire is the evolved form of Swampfire.

Appearance
Ultimate Swampfire appears more of a humanoid tree instead of a walking plant like Swampfire. Ultimate Swampfire's body is dark brown in color, and now has three blue gooey shells containing an organic, blue face, blue colored  gel-like solution on his arms and a large one on his back, that he uses to generate blue colored flames that are about three times hotter than Swampfire's. Ultimate Swampfire's body is composed of petrified wood. Ultimate Swampfire wears the evolved Ultimatrix symbol on his chest.

Powers and Abilities
Ultimate Swampfire is more resistant to damage than Swampfire.

Ultimate Swampfire has lethal fire bombs.

Ultimate Swampfire can fire a huge blue fire blast when he puts his hands together.

In Cosmic Destruction, Ultimate Swampfire can shoot fire bombs that home in on the enemy like missiles, shoot a flamethrower-like stream of fire from both hands, and make a large fire blast either by dropping a fire bomb, or by jumping, releasing several small fire bombs, and punching them down into the ground to create a large fire blast.

Ultimate Swampfire possesses enhanced strength.

Ultimate Swampfire has the same plant abilities as Swampfire.

Ultimate Swampfire seems to be a lot faster than he looks, in Ben 10,000 Returns he snuck up behind Eon so fast that Eon didn't notice him.

Ultimate Swampfire can still grow things on his body, as seen in The Final Battle: Part 2.

Weaknesses
Ultimate Swampfire is shown to be weak to electricity as seen in Ultimate Aggregor and The Forge of Creation when Aggregor used the same attack twice in both episodes.

Unlike Swampfire, Ultimate Swampfire cannot regenerate from damage.

Alien Force

 * Ultimate Swampfire first appeared in The Final Battle: Part 2, when Ultimate Swampfire battled Vilgax. Water then poured into the ship when it went underwater and Vilgax turned into his true form. He then tried to eat Ultimate Swampfire.

Ultimate Alien

 * Ultimate Swampfire returns to "Ultimate Alien" in Ultimate Aggregor, when he and the team break in to take out Aggregor's minions in Los Soledad, in which he easily defeats them.
 * In The Forge of Creation, Ultimate Swampfire was defeated by Ultimate Aggregor.
 * In Eye of the Beholder, Ultimate Swampfire fight the Sentinels and three guardians.
 * In The Big Story, Ultimate Swampfire defeats the Plant Alien with his fire bomb.
 * In Ben 10,000 Returns, Ultimate Swampfire was aged to dust by Eon. Later, Ben 10,000 restores him.
 * In Night of the Living Nightmare, Ultimate Swampfire is seen at the end of the episode confronting Albedo.

Ben 10: Alien Force

 * The Final Battle: Part 2 (first appearance)

Ben 10: Ultimate Alien

 * Ultimate Aggregor (first re-appearance)
 * The Forge of Creation
 * Eye of the Beholder
 * The Big Story
 * Ben 10,000 Returns
 * Night of the Living Nightmare (Dream)

Cosmic Destruction
Ultimate Swampfire is used by Ben during the boss fight against Sunder in Paris on the Eifel Tower.

Toon Football
Ultimate Swampfire is also a toon football player in Toon Football and also the first Ultimate form to be in Toon Football.

Ultimate Crisis
Ultimate Swampfire is the only alien that is used to battle Aggregor and his soldiers.

Project Exonaut
In Project Exonaut, Ultimate Swampfire is an available Exosuit at Level 30. He is on the Banzai Squadron team.

Trivia

 * In a beta Ben 10 action comic cover Ultimate Swampfire appeared to resemble Heatblast, being red, while the napalm shells were yellow.
 * Of all the Ultimate forms, Ultimate Swampfire's physical structure has undergone the most drastic changes (with the exception of Ultimate Echo Echo).
 * Every time Ultimate Swampfire transforms, he bends his arms at his elbows, and holds them upwards while shouting his name (except in The Big Story and in Ben 10,000 Returns).
 * Ultimate Swampfire is the only Ultimate Form used by Ben to appear before Ultimate Alien.
 * Ultimate Swampfire is the first Ultimate Form to be used by Ben, and is also a reference to Ben transforming into fire-based aliens first: Heatblast, Swampfire, and now Ultimate Swampfire.
 * Ultimate Swampfire in Brads opinion is the strongest ultimate form.