in my opinion probaly Fourarms, Benvictor, or Benwolf.
Humungousaur,Way Big and XLR8 oh i fergot Alien X! No, Ultimate Ben is the strongest.
Some fans consider Alien X to be Ben 10's strongest alien due to its reality warping abilities. However, Way Big is also considered one of Ben's most powerful aliens because of his size and strength. Ultimately, the strength of Ben's aliens can vary depending on the situation and how Ben uses their powers.
way big
His name is Waybig, and he is WAY BIG!
ucxn
way big
This guy that can turn bigger and bigger. But way big is way bigger. Way big is 100 feet tall!!!an awesome huge dinosaur alien that smashes stuff on ben 10 alien force.
A ben 10 alien from the secret from the omnitrix movie. Weeie: only the tallest alien is the omnitrix
way big can stomp on him
unluckaly i do not know.i'v never seen an alien merged with him anyway
waybig alien code is=UCXN=
maybe it'll be ultimate way big but right now it's ultimate humongousaur