Help Ben 10 reach the Underworld in this platformer game. Kevin appeared and abducted your cousin Gwen and he demands the Omnitrix in exchange for her life and if Ben chooses to ignore the ransom, Gwen will be killed. Now you must do a one man infiltration to the underworld to retrieve your cousin from danger, and you don't have the help of your alien friends this time around but you can still shoot energy to kill the robotic monsters that are creeping in the dark and delusional underground. Don't get killed or you return to the start of the stage! Ben 10 Underworld is one of our many Action Games that we publish on TheGamerStop.com. This game is also tagged as a Ben 10 game. Click the play button to start having fun. To play even more free games, view our popular and new games page. If you want to play more games like this, then you can simply check out the games inside the game tags that are the most relevant to your interests or the Action Games category or the games like this game page at the end of the game tags.