I'm trying to plan out a team for the Grand Championships at Gencon, but the Tourney rules on Wizkids site haven't been updated since the release of Avengers and LoSH.

Is it a safe assumption that Legacy and Fantastic Forces are going to be retired, or do you just go by what the latest stuff online is?

Fantastic Forces, Legacy, Icons, and Mutant Mayhem will be retired by Gen Con.