If you want to play in the AFCS, you just have to earn a bid. That means winning or placing second in an alliance event, or in one of the big qualifier events, where they give out 4 bids in each age group. 1 bid is all you need, but you have to get it.

If you want a high seed, you need to play more events, log your games in AGL, etc. They also reward points for teams playing against teams from other AGL regions, encourages teams doing events in other regions.

It's just like the college world series - regionals into super regionals.

And once out of super regionals it splits into 3 tiers. the top 2 finishers in each super regional make it to the top level, tier 1. Then everything resets and you start fresh with a new double elim tourney at each of the tiers.