How has it changed?
I haven't spent enough time on it to really tell you details.
I just know because me and a friend got interested in the game again after playing MTG for a while, so we bought these championship decks to see.
The game was way faster, and involved a lot more "strategy" in the abilities and Trainer/Stadium cards.. Raw power and HP was really downplayed, as was the Energy/Color system. I think one of our decks had 4-6 Energy cards in it.
The first set had a feel of slowly "building" up your pokemon with evolution and stuff, while these decks were about abusing combos and stacking of abilities, drawing/playing lots of cards in a single turn.
Keep in mind these were top-tier styles of play, but it's enough to see all the cards from the old set would be absolutely terrible now.
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