As a fixer, this is a really slow and inefficient way to do things, so you probably have to really value the splash of several of the colors towards WUBRG
Plenty of them are obnoxiously powerful in the game itself, too
For example, about halfway through the game, I decided to look up a deck build
One Piece TCG: Emperors in the New World - Booster Pack OP-09 One Piece TCG: Emperors in the New World - Booster Pack OP-09 Bandai Please Note: This product is brand new & factory sealed
It also has an effect that allows the player to find three energies from their deck and attach it to any of their V Pokmon in any way they desire
Partially this is because of nostalgia, with Pokmon Ruby, Sapphire and Emerald being a lot of people's first Pokmon games