Tournament rulesets (SSB)
Please note that as per mid/late 2015 all stages outside of Dream Land were banned after a collective effort by TOs of the community along with members of the backroom. Prior, Kongo Jungle, Hyrule Castle, and Peach's Castle were occasionally legal. The ruleset below is for post these years. Please see Apex 2012 an an example of an pre-backroom ruleset
Low tier ruleset, emulation legality and other various rules
The Waterfall Bracket (otherwise known as the WTF Bracket) is a bracket style designed to let everyone attending the tournament be able to play a lot of matches against players of similar skill. It was created by Shears and Dark Gentleman and became popular in 2017 and was used in most majors since then.
There is the option to start off with a Placement Pools where pools of 5 to 8 people play Round Robin style. The pools are designed to contain 1 elite player, a couple well respected players that aren't elite yet and the rest of the players beginner level. After that placement pool - or by seeding if there is no placement pool - the attendees are put into different rounds of round robin pools: The tournament is then separated into multiple divisions (for example 4 divisions, usually named by numbers 1-4) with multiple round robin pools in each division (for example 4 pools, named 1A-1D for division 1). The lowest seeded players / worst players in placement pools are put into the pools lowest division (for example division 4), the highest seeded players start in the first division (1). The matches of the lowest divisions are played first then and the best players in each pool make it into the next highest division (for example from division 4 to division 3) and the other players are out of the tournament. Then the next divisions are played one after the other and the best players of division A's pools usually play a top 8/16/24/32/64 double elimination bracket.
More recently, these brackets have been ran without the Placement Pools due to players (such as SuPeRbOoMfAn and others at Shine 2018) sandbagging to get extra practice. Players are seeded by conceived skill and advance as per above to the next pool if they do well enough in their division.