Because his name is Ben Tennyson and he can transform into 10 different aliens. But now he ca turn into like 20 different monsters.
first Ben has 10 aliens, his las name is Tennyson and the whole Ben ten rhyming thing going on plus hes 10 years old...thus Ben 10 (catchy right)
yes he will die. ***SPOILER*** what happens is all the aliens in his watch come out and turn bad and kill ben his sister and his grandad and they are just destroying earth.
Ben is 10 years old.
Ben 10 Aliens Wildmutt Fourarms GraymatterXLR8 Upgrade Dimondhead Ripjaws Stinkfly Ghostfreak Heatblast GoopSwampfireChromastoneBigchillHumungousourBrainstormJetray SpidermonkeyEchoechoAlienX