At first glance, 10-year-old Ben looks like your average, everyday kid, but upon closer inspection it's plain to see he's the world's youngest action hero stopping evildoers from Earth and space! With the help of the Omnitrix, Ben can transform into heroic alien forms with extraordinary powers. The evil Vilgax, with the help of Kevin 11 and the Forever Knights, has set in motion a plan to capture the Omnitrix and the world is in danger…Ben 10: Protector of Earth is an exciting game full of familiar characters on a quest to stop Vilgax and save the day!

Ben begins with Fourarms and Heatblast and as the game progresses, with XLR8, Cannonbolt and Wildvine. In the beginning, Ben can stay an alien for a limited amount of time, but after defeating some bosses, Ben can stay alien for an infinite amount of time or switch between aliens without draining Omnitrix energy. Attack combos can be unlocked collecting Omnitrix points. Limited power boosts or invincibility can be gathered, as well as bonuses to make the Omnitrix recharge faster. Sumo Slammer cards are hidden in each main level and once collected unlock special features.

After each level, Plumber ranks are rewarded, depending on how fast the player beats that level. In the main boss levels, a God of War styled button sequence allows players to execute a special attack at certain points. (Wikipedia)

Passwords

In game cheats
Press start while choosing a mission and choose Extras and choose Enter Secret Code

Cannonbolt; Cannonbolt; 4arms; Heatblast - Dark Heroes

Wildvine, Fourarms, Heatblast, Cannonbolt - DNA Force

XLR8 ;Heatblast; Wildvine; 4Arms - Invincibility

Cannonbolt,heatblast,wildvine,4arms - Master Control

wildvine,4arms,heatblast,wildvine - unlock alien forms

Cannonbolt; Heatblast; 4arms; Heatblast - Unlock ALL Combos

Heatblast; XLR8; XLR8; Cannonbolt - Unlock All Locations on Map

Here's a fanmade trailer of an original Cartoon Network-based title: