Leffen

William Peter Hjelte (born 16 October 1994), better known by his gamertag Leffen, is a Swedish professional fighting game player and streamer. Although mostly known as a Super Smash Bros. Melee player, he has also competed in Dragon Ball FighterZ, Guilty Gear Strive, and Super Smash Bros. Ultimate. In Melee, Hjelte plays the character Fox, and is considered one of the best players in the world, having been ranked as one of the top seven Melee players in the world every year since 2014. A 2021 list compiled by PGstats ranked Hjelte as the sixth greatest Melee player of all time.

A Super Smash Bros. competitive player since 2009, he rose to international success in 2014, becoming the first player to beat each of the "Five Gods of Melee" —Armada, Mew2King, Hungrybox, Mang0, and PPMD— in tournaments over the course of his career (a feat only accomplished since by Plup), earning him the nickname of "God Slayer". He has won many tournaments ranked as majors in his career, starting with the Swedish tournament B.E.A.S.T 4 in 2014, which saw him become the first person other than one of the Five Gods to win a major since 2008. Since then, some of his most notable tournament wins include the 2015 and 2019 editions of Super Smash Con, CEO 2015, and Evo 2018. Since Armada's retirement in 2018, Leffen has been considered the undisputed best Melee player in Europe.

Although recognized as one of the best players in Melee history and having a dedicated fan base, Leffen has also been considered one of the most controversial and polarizing players in Super Smash Bros. history, due in part to accusations of aggressive and anti-social behavior— which resulted in a temporary ban from the Swedish competitive Melee scene in 2013. As a result, he has been referred to as the "Villain of Super Smash Bros."