Vilgax is an intergalactic alien warlord and conqueror that seeks to obtain the Omnitrix and the overall main antagonist of Ben 10, serving as the main antagonist of the first two seasons and the movie Ben 10 Versus the Universe: The Movie.

Vilgax is a muscular squid-like alien. His appearance is mostly similar to his Original Series counterpart; however, he has red veins across his arms, and his mouth is visible. His tentacles are also darker at the ends. He wears a brown-black armored suit and fingerless gloves. His armor is spiked at the shoulder pads, and he also has spikes on his forearms.

In his incomplete form, Vil is a very slim frail-looking old man who wears a purple cloak. He was rather short and hunched back a bit. He also had very skinny feet.

As of Out to Launch, Vilgax has blackened dark patches of flesh down his left side - a permanent reminder of his first defeat at the hands of Ben.

In The 11th Alien, Super-Villain Team-Up, and Ben 10 Versus the Universe: The Movie, Vilgax wears a tattered cloak resembling the one he used to wear as Vil.

During Ben 10 Versus the Universe: The Movie, Vilgax temporarily gains possession of the Antitrix.

When Vilgax used to work with Azmuth, he wore white goggles on the top of his head as well as a cloak.

In the past when he wielded the Omnitrix, Vilgax wore shoulder pads on his cloak and occasionally wore a respirator.