Retcons

Throughout the Ben 10 franchise, various changes in the continuity, otherwise known as retcons, have been made. Below are most of the retcons made in the franchise. According to Matt Wayne, they take what they want and ignore what they don't like.

Ben 10: Alien Force

 * The Plumbers are now an intergalactic police force, when it was established in the original series that they were a secret government organisation comprised of humans only, and several with a racist attitude towards aliens.
 * Gwen's powers are now alien in origin, inherited from her grandmother Verdona, as well as magical.
 * Kevin's backstory, species, and his power's origin have been altered for the series.
 * He is now an Alien hybrid with the ability to absorb a shell of material around his body instead of a mutant that has the ability of absorbing, storing, and redirecting energy.
 * His father Devlin Levin is a Plumber that he received his powers from and was partners with Max instead of a mutation that no-one knew where it originated from and it is responsible for his parents to kick him out.
 * The Forever Knights now have different factions instead of being one whole group.

Ben 10: Ultimate Alien

 * It is revealed that Kevin's stepfather is actually a good person and that Kevin wasn't kicked out, but he went insane with power, destroyed the house, and ran away.
 * The queen in Ben 10: Alien Swarm has been changed into a decoy queen created by the real queen to avert suspicion towards her.
 * Ben 10: Race Against Time has been retconned into an alternate timeline.
 * Eon was changed into an alternate version of Ben.
 * Chronians do not exist anymore.
 * Ben's future has changed.

Ben 10: Omniverse

 * The origin of the Galvanic Mechamorphs was revised from the original toy info.
 * Ben's last encounter with Vilgax was when he was 11, though it was established in Alien Force that he last met him when he was 10.
 * Max never met Kevin's dad, who didn't even exist - it was all a fake memory made by Servantis.
 * Osmosians are no longer aliens; rather, they are humans with a unique genetic component that gives them powers.
 * Ben's future has changed back into the future that he originally had in the original series. However, some elements of the future depicted in the original series were revised.
 * Ben 10,000 and Kai Green (Future) now have only one child, Ken Tennyson (Future).
 * The Plumbers' Helpers now have different origins.