Alphonse Elric
That's My Rule!!!
Of course they die. 
Hey, imagine some stupid fricking Pokemon living forever? That's plain impossible. Butterfree die after mating, meaning that Ash's Butterfree died a long time ago. Then there's the Marowak, and then Latios, and Lucario. In fact, I believe Celebi also died in the uncut Japanese Version... So basically, yeah, Pokemon die. I mean, what do you expect, they have organs that never decompose, or hormones and cells that never disintegrate? Bah, death is natural anyways... and overrated.
Hey, imagine some stupid fricking Pokemon living forever? That's plain impossible. Butterfree die after mating, meaning that Ash's Butterfree died a long time ago. Then there's the Marowak, and then Latios, and Lucario. In fact, I believe Celebi also died in the uncut Japanese Version... So basically, yeah, Pokemon die. I mean, what do you expect, they have organs that never decompose, or hormones and cells that never disintegrate? Bah, death is natural anyways... and overrated.