People in this thread seem to be ragging on about how pokemon hasn't changed, comparing it to the formulaic CoD series. I don't think that comparison is adequate. Since CoD hit it big with Modern Warfare it has been a bland but enjoyable modern shooter, with a shift to a futuristic setting in more recent years. The core gameplay has remained the same. Shoot x amount of bad guys, press x to not die. Repeat. Multiplayer hasn't had any significant changes either. Most of the guns act in the same way (point and pull trigger until it dies or you do), the killstreaks still follow the same formula and there's been minimal changes to the mechanics of multiplayer.

Pokemon on the other hand, started out with 15 base types and 151 pokemon. Since then there's been 568 pokemon released, 3 new base types added and hundreds of moves added. New mechanics have also been added. 4x damage never existed in the first game, neither did 4x resistances. Held items and abilities are new too, and who could forget the awesome power of Mega Evolutions and the effect they have had on the game.

Every time a new pokemon game is released, the multiplayer pokemon scene gets reinvented. New strategies become viable, old strategies die out in the face of new counters and checks. Your strategy is only limited by your creativity and what you can legitimately create to battle with.

Meanwhile the only real gameplay change I've seen from CoD in the 6 years since I last played it regularly has been "I'll shoot things... with a jetpack".