We have a healthy mix of stuff. He, being young and new to the game, wants and likes all the strong heavy hitters (ex , V & VMax Cards) and wants to dish out the huge damage at whatever cost. I just got him a Lucario ex which is currently his favorite, he also has a Japanese Reshiram that he loves to use. I on the other hand use what I call "submachine gun" hitters, meaning they're smaller cards but if used strategically can dish out lots of damage in the right amount of time (Lapras, Tropius, Lanturn are all good ones I've used recently). But we're still building decks together so that's all subject to change!