Echo Echo

Echo Echo is a Sonorosian alien from the planet Sonorosia.

Ben first transformed into Echo Echo during episode Ben 10 Returns: Part 2 when fighting Forever Knights.

Appearance
Echo Echo is a small white alien whose body is a living amplifier. One of the most noticeable features is a square appendage resembling an MP3 player behind his back with a port on it - decorated with a IO symbol, and what looks like cassette tapes on his lower legs. It was also revealed in Fool's Gold that Echo Echo is made out of silicon which allowed him to defeat Decka.

Powers and Abilities
Echo Echo can scream at ultrasonic frequencies capable of overloading machinery and stopping projectiles in mid-flight. He also has the ability to duplicate himself, not unlike Ditto, but different in that the clones aren't linked in any way, allowing entire groups to be knocked out without hampering the rest. His cloning capabilities seems limitless. By combining these two aspects, Echo Echo can create a "Wall of Sound", where he and his clones can redirect projectiles back to their source by bouncing them off of strategically placed clones, and "Echo Chamber", where he and his clones attack from all directions, and keep sending out sonic screams until the victim is knocked out or defeated (In a circle, as seen in Above and Beyond).

Echo Echo can also use echolocation, as seen in Alone Together, and can channel vibrations to enhance his power, as seen in Undercover.

He can transmit sound waves through speakers (such as phones), as seen in Grounded. Echo Echo can also detect vibrations in the ground. They have to go back into one body before transforming back to Ben like Ditto or else the clones become multiple personalities as seen in Duped. Echo Echo is also quite agile, using his size as an advantage against large opponents. It seems he has more strength than his size suggests, as he can he kick off a whole trunk door from Ben's car in Absolute Power: Part 2, and can jump pretty high.thumb|right|266px|Echo Echo transformation

Ultimate Alien
He first reappeared in Duped, only to create three different Ben's. He made another small appearance in Map of Infinity, to transform into Ultimate Echo Echo. He reappeared in Nor Iron Bars a Cage for an actual appearance to stop the sonic electro collars on the prisoners. This is the first time that he uses his sonic screams while talking. He appeared again in "The Enemy of My Enemy " to get rid of the nuclear fusion grenade but failed so he went Ultimate. He appeared again in "Absolute Power: Part 2 " to fight Kevin but all Echo Echo clones were killed so the spare Echo Echo clone in the trunk hops out of the car and goes ultimate.

Ben 10: Alien Force

 * Ben 10 Returns: Part 2 (first appearance)
 * Kevin's Big Score
 * Darkstar Rising
 * Alone Together
 * Good Copy, Bad Copy (used by Albedo)
 * Undercover
 * Grounded
 * Unearthed
 * Fool's Gold
 * Don't Fear the Repo (selected alien was Humongousaur)
 * Single-Handed
 * Trade-Off
 * The Secret of Chromastone
 * Above and Beyond

Ben 10: Ultimate Alien
''
 * Fame (video footage)
 * Duped x2
 * Map of Infinity
 * ...Nor Iron Bars a Cage
 * The Enemy of My Enemy
 * ''Absolute Power: Part 2
 * Vicktor The Spoils ( selected alien was Humongasur)
 * The Big Story

Video Game Appearances

 * Ben 10: Alien Force The Video Game (He is playable on DS)
 * Ben 10 Alien Force: Vilgax Attacks
 * Ben 10 Alien Force: The Rise of Hex
 * Ben 10 Ultimate Alien: Cosmic Destruction

Trivia

 * He is made of silicon.
 * The Echo in his name could stand for his powers of sound and duplication. Also if you say echo in a cavernous space it will "echo" back to you making it sound like "Echo Echo".
 * In Alien Force, He appeared in 14 episodes.
 * He is the first of Ben's aliens to answer his cellphone, Rath was the second.
 * He is also the first alien used by Ben to jump into another aliens stomach, the second being Rath in Con of Rath.
 * Echo Echo is the third alien with the self-duplication ability. The first being Buzzshock and the second being Ditto.
 * Dwayne McDuffie confirmed it's his favorite Ben 10: Alien Force alien.
 * As it was stated that upon recalibrating that the Omnitrix gave Ben new alien forms similar to those he had in the original series, Echo Echo could be given in place for Ditto's self duplication, Benwolf for the sonic screech and Upchuck for his size.
 * "Wall of Sound" is an unlockable combo move in the video game Vilgax Attacks.
 * Sometimes when Ben transforms into Echo Echo he immediately duplicates.
 * While Echo Echo has self-duplication, he loses it when he evolves. The duplicates instead become sonic discs.
 * Like in Duped, it is possible than when three Echo Echo clones go ultimate at once, there will be duplicates of Ultimate Echo Echo. It is unknown whether Ben will ever think of this, let alone try it.
 * Unlike Ditto, when one of Echo Echo's clones are injured, it has no effect on the others. One example of this is when Echo Echo's clones are put to sleep by Argit, the others remain awake. This means that if one clone dies the others will live, not the same for Ditto however.
 * In Absolute Power: Part 2, Kevin killed all the Echo Echo clones surrounding him. However, Ben reveals that he keeps a spare Echo Echo clone in his car if this would happen.
 * Dwayne McDuffie confirmed Echo Echo has headphones so he isn't damaged by his powers.