Goop

Goop is the Codon Stream's DNA sample of a Polymorph from the planet Viscosia.

Appearance
Goop is a humanoid pile of goop that can take any shape.

Goop wears the Omnitrix/Ultimatrix symbol on his chest.

Powers and Abilities
Goop controls his slime with his Anti-Gravity Projector, if Goop and the Anti-Gravity Projector are separated by at least two feet, Goop's body will become inert until the Anti-Gravity Projector recollects it.

Goop's Anti-Gravity Projector allows Goop to take any shape and fly.

Goop can manipulate his Anti-Gravity Projector to fly away and cut enemies.

In Vilgax Attacks, Goop can throw a blob of goo at the enemy, spray acid from his hand like a hose, and spin his feet around to damage nearby enemies.

If Goop loses his Anti-Gravity Projector when going through an obstacle, the Omnitrix/Ultimatrix can create a new one instantly.

Goop is able to fire slime with acidic or sticky properties upon impact.

Goop can use his acid like abilities to destroy nearly anything.

Weaknesses
Goop is limited to his Anti-Gravity Projector controlling his body. If it is separated by two feet, more or turned off, Goop's body goes completely inert.

It is shown Goop can be hurt by being spun really fast.

Because of his slime body, the Omnitrix/Ultimatrix can be easily pulled off and reverting Goop to normal and removing the Omnitrix/Ultimatrix from the user.

Alien Force

 * Goop first appeared in The Gauntlet, to defeat a blue Techadon.
 * In Darkstar Rising, Goop battled Magister Gilhil.
 * In Good Copy, Bad Copy, Negative Goop was roaming around a computer store. Goop battled Negative Humungousaur.
 * In Undercover, Goop saved Cooper from some DNAliens.
 * In Birds of a Feather, Goop helped Simian escape from some guards.
 * In Vengeance of Vilgax: Part 2, Goop escaped from the Omnitrix and hid in the sewers. He battled Swampfire before getting reabsorbed.
 * In Fool's Gold, Goop appeared to battle Mayor Coleman.
 * In Simple, Goop to save himself from getting hurt.
 * In Don't Fear the Repo, Goop battled the Vreedle Brothers.
 * In Single-Handed, Ben turns into Goop while Julie is using his hand as a weapon, disgusting her.
 * In In Charm's Way, Goop battled Charmcaster's rock monsters.
 * In Primus, Ben turned Vilgax into Goop and pulled the Omnitrix off his chest, removing the Omnitrix from Vilgax.
 * In Above and Beyond, Goop defeated Pierce.

Ultimate Alien

 * Goop returned to Ultimate Alien in Andreas’ Fault, Goop escaped a dungeon cell.
 * In Hero Time, Goop saved Julie from falling.
 * In Deep, Goop failed to escape some fans until Gwen saved him. Goop used his Anti-Gravity Disk to save Piscciss. Although Goop was atomized and spread throughout the planet's water, he survived and was able to pull Piscciss back together.
 * In Nor Iron Bars a Cage, Goop escaped a locked room and unlocked the door to let Gwen out.
 * In Viktor: The Spoils, Goop appeared as King Xarion was looking through the Ultimatrix for AmpFibian.
 * In Revenge of the Swarm, Goop battled the Victor Validus clones. As soon as Goop tried to catch him, Victor escaped.
 * In The Creature From Beyond, Goop saved Gwen and Kevin.
 * In Ben 10,000 Returns, Goop battled Eon's servants.
 * In Greetings From Techadon, Goop battled the yellow Techadon.
 * In The Perfect Girlfriend, Goop was defeated by Ssserpent.
 * In Catch a Falling Star, Goop was used to break into the motel room of Carl Nesmith and Jennifer Nocturne.
 * In Night of the Living Nightmare, Goop was used to battle Vilgax.
 * In The Beginning of the End, Goop was used to defeat the Forever Knights.

Ben 10: Alien Force

 * The Gauntlet (first appearance)
 * Darkstar Rising
 * Good Copy, Bad Copy (used by Albedo and Ben)
 * Undercover
 * Birds of a Feather
 * Vengeance of Vilgax: Part 2 (escaped)
 * Fool's Gold
 * Simple
 * Don't Fear the Repo
 * Single-Handed
 * In Charm's Way (accidental transformation, selected alien was Way Big)
 * Primus (used by Vilgax)
 * Above and Beyond

Ben 10: Ultimate Alien

 * Andreas’ Fault (first re-appearance)
 * Hero Time
 * Deep (x2)
 * Nor Iron Bars a Cage
 * Viktor: The Spoils (cameo; unconscious)
 * Revenge of the Swarm
 * The Creature From Beyond
 * Ben 10,000 Returns (Intended alien was Rath)
 * Greetings From Techadon
 * The Perfect Girlfriend
 * Catch a Falling Star (cameo)
 * Night of the Living Nightmare (Dream)
 * The Beginning of the End

Specials

 * Ben 10-Generator Rex: Heroes United (flashback)

Trivia

 * According to Dwayne, Goop is a single celled organism.
 * Goop's Anti-Gravity Projector isn't part of Polymorph biology; this is due to the difference of gravity between Viscosia and Earth.
 * Although he can shapeshift, Goop's humanoid state appears to be his "default" shape.
 * Goop's Anti-Gravity Projector became a substitute for the missing Anti-Gravity Multiplier on planet Piscciss.
 * Goop's voice is similar to that of Stinkfly.
 * In The Beginning of the End, Goop believes his voice prevents others from taking him seriously.