Ben 10 - Season 2 - Eps 8: Ultimate Weapon
In Texas, a group of men discover a mysterious mask belonging to Ah Puch, the Mayan god of death and destruction. The mask is the key to the ultimate weapon in the world, known as the Sword of Ekchuah. However, when Grandpa Max and his grandkids learn that the mask is discovered, he impatiently sets out to obtain the mask, so that it does not fall in the wrong hands. Unfortunately, they find out that Enoch of The Organization is after it as well. The kids worry of how Grandpa Max has become, but with Enoch in the way, will Grandpa Max find the sword before him?
About Ben 10

Title: Ben 10
First Air Date: 2005-12-27
Last Air Date: 2008-04-15
Status: Ended
Rating: 8.166/10 (from 1676 votes)
Language: EN
Seasons: 5
Total Episodes: 52
Network: Cartoon Network
Genres: Animation, Sci-Fi & Fantasy, Action & Adventure, Comedy, Kids
Production Companies: Cartoon Network Studios, Man of Action Entertainment
Synopsis
When 10-year-old Ben Tennyson discovers a mysterious device, he gains the power to change into ten different alien heroes, each with uniquely awesome powers. With such abilities at his disposal, Ben realizes a greater responsibility to help others and stop evildoers, but that doesn't mean he's above a little superpowered mischief now and then.
Cast

Tara Strong
Ben Tennyson (voice)

Meagan Moore
Gwen Tennyson (voice)

Paul Eiding
Grandpa Max (voice)