>>95104681Popular unofficial competetive rule set.
The official competetive pokemon format is 2v2 so if you want to play normal battles competetively Smogon is the only real choice.
Pokemon are placed in to tiers by usage and while you're free to use mons from lower tiers, you can't use ones that are above the tier you're playing in.
OU is the highest tier and thus the standard tier and there are 6 tiers below it, all of them having their own metas. There's a "tier" above OU called Ubers where all the pokemon that were banned from OU (or were never even allowed) go.
