Ruby & Sapphire stuff. The EX era was the best of Pokemon TCG IMO. So many playable, versatile cards, powerful yet tame combinations that really allowed the skill of players to shine, and not just 15 minute first turn donks or single energy sweeping.
Blaziken EX, Metagross EX, Energy Draw Delcatty, Pidgeot FRLG, Cradily EX, Medicham EX, Rocket's Pokemon, Team Magma/Aqua, too many to list really. The playable Pokemon were also a lot more varied, and not always Gengar/Garchomp/Machamp. The diversity allowed people to have pride in the deck they played, and the cards were balanced and there would be means of making it competitive.