The Antitrix allows Kevin to transform into 11 aliens, most of which are ones that Ben has used before, but significantly altered from Ben's version.
What are the Ben 10 aliens called?
Phil has created a helicopter called the "Omni-Copter" for the Tennyson Trio so they can travel around the world. Ben also gains access to three new aliens: Rath, Slapback, and Humungosaur, who replace Grey Matter, Overflow, and Wildvine.
How many aliens does Ben 10 Ultimate Alien have?
30 Aliens - Swampfire, Jetray, Chromastone, Humungousaur, SpiderMonkey, Echo Echo, Brainstorm, Alien X, Big Chill, Goop, Ultimate Humungousaur, Ultimate SpiderMonkey, Ultimate Echo-Echo, Ultimate Big Chill, Ultimate Swampfire, Ultimate Cannonbolt, Cannonbolt, Rath, Lodestar, Murk Upchuck, Water Hazard, NRG, Armodrillo, ...
How many aliens does Ben 10 have in the original series?
At first, there are only ten aliens (hence the name "Ben 10"), but more forms were discovered as the series goes on.