Competitive is different. You can play an attrition team, where every opponent switch hurt him, or a clone+relay team (my favorite) where you stack attack buffs then use relay to transfer them to your hard hitter. You can play a mix of those, or just good pokemons with tight strategy (the equivalent of Jund zoo basically if you're a MTG player)

Unless you talk about pokemon TCG, and in this case, 8 don't know.