Board Thread:General Discussion/@comment-5486221-20131130071758/@comment-10870881-20131203225303

Alex10alienomniverse wrote: I don't know why ben didn't use articguana in ultimate alien.He could and also could use all ultimate forms. Something I posted on another thread;

Ben said that he was afraid of his Ultimate forms, which was justified eventually.

http://ben10.wikia.com/wiki/The_Ultimate_Sacrifice

My theory is that either afterwards Ben was afraid to use any more Ultimates because they might become sentient too, or Azmuth disabled all further Ultimates he hadn't already used. And Ultimate Way Big was unlocked off screen earlier or given to Ben before fighting Diagon.