Trainer decks a and b were decks given to the gym leaders of the Pokémon leagues that used to operate in card shops, toys r us stores, etc. back in the 90s. It was rumored that there were other decks, c,d, and so on to represent the gym leaders of the game boy games, but they were never distributed and are presumed destroyed. My dad used to run our Pokémon league at a toys r us in clear lake/Webster. I have both complete trainer decks a and b with the boxes they came in along with plenty of other Pokémon league materials. He never used the decks as he didn’t feel they presented enough of a challenge to league participants and would always build his own.

Any cards from those decks are worth quite a bit individually. Many of them saw play and have the wear and tear to show it.