Praise be to Allah.
Pokemon is clearly a kind of gambling, in addition to the fact that it includes symbols of atheist belief whereby the heavens are almost torn, and the earth is split asunder, and the mountains fall in ruins [cf. Maryam 19:90]. Exalted and sanctified be Allaah far above what the wrongdoers say.
With regard to it being a form of gambling, that is when two people play this game and each one competes to win what the other one has of certain pieces which can be redeemed (for cash) at toy stores, the value of which is established by a process which is subject to the rules of supply and demand. They may also be redeemed for other things, such as some fast foods or tinned goods. The winning player may also offer them for sale to the losers so that they can play again and so that the one who loses can get out of the game. Undoubtedly this is the essence of gambling. This game is teaching the children of the world how to gamble and commit evil and immoral actions.