The FFIC uses a rotating pool of different types of leagues in order to test the overall knowledge of participants. Selections from each tier are rotated in order to create maximum diversity between seasons and prevent participants from having to play in the same league types repeatedly. The league pool is broken into four tier groups according to factors such as player retention, required fees, and complexity levels. Each season 10 of the leagues will be selected at random for players to participate in. Here's how those tier groups are broken out (click on a league name in the tables below for more details about that specific league)...
Long-Term Tier 
Each season participants will play in two leagues that focus on the strategy of player retention. These long-term league types will always make up two of the twelve leagues for the competition.
MFL Fee Tier 
Due to the customization needs of some league types, all leagues that require settings only available on MFL have been grouped into a single tier. Two of these will be used each year; however, the annual fee will be limited to only $60. League types in this tier will be selected at random each year with no repeat from one year to the next.
Standard Tier 
The Standard Tier focuses in on league types that are the most common. While there are variations between these leagues, they are standard to most fantasy football players and in most cases, they are the least challenging of all the league types. Four of these leagues will be used annually with no repeat selections from one year to the next.
Variety Tier 
The Variety Tier is composed of leagues that are the farthest from a standard league type. These are leagues based around odd rule sets that can get out of hand quickly if everyone playing doesn't bring their A-game. Four of these leagues will be used annually with no repeat selections from one year to the next.