its either Ultimate Humoungousaur or Ultimate XLR8.
EDIT BY UNDEADAWE: XLR8 cant go ultimate, lol. Anyways, Ultimate Ben is the best, fact, not opinion.
The best alien is Ultimate way big
THE best alien of ben-10 ultimate alien is alien x.
maybe it'll be ultimate way big but right now it's ultimate humongousaur
"The Ultimate Enemy Part 2" is the Final episode of Ben 10 Ultimate Alien.
Dwyne MicDuffie is the producer of "Ben 10 ultimate Alien". He is dead now.
NO
Humungousaur,Way Big and XLR8 oh i fergot Alien X! No, Ultimate Ben is the strongest.
Ben 10 ultimate alien.
Ben 10 Ultimate Alien - 2010 is rated/received certificates of: Australia:PG
Ben 10 Ultimate Alien - 2010 Ultimate Aggregor 1-10 was released on: USA: 10 October 2010
yes Ben can turn into Xlr8 in ultimate alien tv show
Swampfire Ultimate SwampfireHumangasaur Ultimate HumangasaurBrainstorm Ultimate Way BigBig Chill GoopJetray U.Big ChillEcho EchoWay Big Ultimate Spider monkeyBloxx FourarmsRathLodestar Ultimate cannonboltFeedbackGravattack DiamondheadBall WeevilShocksquatch CannonboltBenwolf HeatblastBuzzshockAlien XNanomechNRGArmodrilloWater hazardTerraspinAmphibianCrashhopperKickin HawkAstrodactylJury RiggClockworkFasttrackEatleChamAlien/Overkill
Nope