Leffen at EVO 2018.
|Ultimate main||Pokémon Trainer|
|SSB4 mains||Diddy Kong, Pikachu|
|Brawl main||Diddy Kong|
|Falco, Yoshi, Marth|
|Project M mains||Fox, Zero Suit Samus|
|Other Project M
|Former sponsor(s)||Red Bull|
|Skill|| Top level |
High level (retired)
Upper high level (retired)
Upper high level (retired)
|Ranking|| SSBMRank 2022: 7th |
|Winnings|| ~$137,640.87 |
|Real name||William Hjelte|
|Location||Stockholm, Stockholms Län|
Leffen is a professional smasher from Stockholm, Sweden. He is currently considered to be one of the best Melee players in the world and the best player in Europe. He started off as a Falco main, but later switched to Fox, and is now known as one of the best and most technical Fox players in the world and one of the best Sheik players in the world, using Sheik as a counterpick to Marth. He is the first of only two players in competitive Melee history to have taken a set off of each of the Five Gods (the other being Plup), and has often been called a god himself since his ascent in 2014. Leffen is currently ranked 1st on the Swedish Melee Power Rankings, 1st on the European Melee Power Rankings, and 7th on the SSBMRank 2022.
Although Leffen didn't play Brawl competitively and only went to a few Smash 4 tournaments, he was active in Ultimate for the game's first year, maining Pokémon Trainer and briefly touching Pichu and Roy. During this period, he was considered one of the best Pokémon Trainer players in the world along with Tweek, moxi, and Ned. Leffen has defeated players such as Tweek, Salem, WaDi, Puppeh, Mr.R, Maister, ZD, and 8BitMan. He is listed an Honorable Mention on both the Swedish Ultimate Power Rankings and the European Smash Rankings; he was also formerly ranked in the Area 51 position on the Fall 2019 PGRU.
Leffen's introduction to Smash was through Brawl, which he played online in 2009.
In 2010, he started attending tournaments for Melee. He mained Falco and also trained a Yoshi secondary, which he used to great success at Stockholm locals and at Danish events.
Leffen's first stateside outing was at GENESIS 2. After defeating SFAT in pools, he went on to lose to SFAT and S2J in bracket to place 17th.
Apex 2012 was Leffen's first serious event as a Fox main. Leffen reached bracket, then lost a last-hit set to Mew2King in winners. He went on to lose his next set to Teczero.
Throughout the course of 2012, Leffen established himself as Europe's second strongest player, with key results at Smashers' Reunion: Melee Grande and at hf.lan 4. He sparred often with Armada, making headway but never taking a set. He came closest at Beauty 6 in January 2013, where he was leading winners' finals 3-2 (in a best-of-7) and brought the sixth game to last stock before Armada clutched out the victory, going on to win the set 4-3.
At Apex 2013, Leffen defeated MacD and Cactuar in winners to meet Hungrybox. He made a splash by bringing Hungrybox to last hit but would lose this set as well. This close loss would go on to inspire a Salty Suite rematch the following year. In losers, Leffen immediately lost another last-hit set, this time to JAVI.
Soon thereafter, Leffen was banned from many European tournaments by a group of organizers and Smashers, largely led by Armada (discussed in greater detail here). He attended only three more events for the rest of the year. He traveled to Evo 2013, defeating PewPewU before losing again to Hungrybox, this time without taking a game, and to Shroomed in losers to place 9th. He and Ice scored an upset victory in doubles against eventual victors Mew2King and Hungrybox; the European team would go on to place 5th.
Leffen also attended an NYC local in September called CFST: Warzone 2, where he suffered unusual losses to MattDotZeb and G$, perhaps due to lack of practice. He finished out the year at the French hf.lan 6 where he placed second, defeating Baxon and Salepate convincingly before losing two close sets to Ice. Given his powerful play despite his scarce results, Leffen was ranked 14th on the 2013 SSBMRank.
Leffen's ban ended early in 2014, allowing him to compete in Europe again.
Emergence as a top 6 player
On day 1 at Apex 2014, Leffen and Hungrybox played in a Salty Suite set, which Hungrybox won 3-1. In bracket, Leffen defeated Darrell, Scar, and Axe before finally taking revenge on Hungrybox 2-1 in winners' quarters to reach top 8 and earn his first win over one of "the Five Gods". He went on to lose to Mew2King 1-3 in winners' semis. He eliminated Colbol 2-0 in losers' quarters, and then had a close and intense set with Mango in losers' semis, but was ultimately eliminated 2-3. This 4th place showing immediately confirmed Leffen as a player to watch for the rest of the year and would presage his ascent to godhood.
Leffen won his first European national at B.E.A.S.T 4, which was also his first European tournament after his ban was lifted. He lost to Ice 2-3 in winners' semis, but then eliminated Fuzzyness 3-0 in losers' quarters, Overtriforce 3-1 in losers' semis, and Ice 3-2 in a rematch in losers' finals. In grand finals, he managed to win two sets against Armada, 3-0 and 3-1, respectively. This marked his second "god" victory. Later, Leffen won Republic of Fighters 3, qualifying for the MLG Anaheim 2014 championship bracket. He defeated Ice 3-1 in winners' semis, but lost to Armada 0-3 in winners' finals. After eliminating aMSa 3-2 in losers' finals, he came back and won 6-0 against Armada in two best of 5 sets.
In his pool at MLG Anaheim 2014, Leffen defeated PPMD 3-2 (the third "god" he had beaten), Axe 3-1, Colbol 3-1, s0ft 3-0, and Remen 3-0, but lost to Mew2King 1-3 and Hax 2-3. Seeded in losers' bracket in the championship bracket, he defeated both Westballz and Hax 3-2, before losing to PPMD 1-3 in losers' quarters, placing 5th overall. At EVO 2014, Leffen defeated Lambchops 2-1, OkamiBW 2-0, and S2J 2-0 in the winners' quarters pools, but lost to Mew2King 0-2. In losers' bracket, he was eliminated by Silent Wolf 1-2, finishing off at an underwhelming 9th place overall.
At COMEBACK I, Leffen defeated Android 3-0 in winners' semis to make it to winners' finals against Armada, in which he lost 1-3. After defeating Android 3-1 in losers' finals, he lost again to Armada in grand finals, this time 2-3, placing 2nd in Melee singles. Leffen also won Melee doubles with Beat, defeating Dev and Kuja 3-1 in winners' semis, Android and Zoler 3-1 in winners' finals, and Armada and C 3-1 in grand finals.
At The Big House 4, Leffen defeated Hungrybox 3-2 in winners' quarters to advance to winners' semis. He then faced off against Armada in another close set, ultimately managing to clench out a victory 3-2 and advance to winners' finals for the first time at an American national. However, he lost 0-3 to Mew2King in winners' finals and 1-3 to Mango in losers' finals, with a 4-stock by Mango to close out the set.
At B.E.A.S.T 5, Leffen managed to solidly defeat Armada 3-1 in winners' semis to advance to winners' finals. He managed to take his first victory over Mango in a 3-2 set to advance to grand finals, where he would once again face Armada. Despite a closely fought set from both players (with Armada notably 4-stocking Leffen in game 4), Leffen managed to win grand finals 3-2, earning his first national victory with at least two of the "gods" present.
After this 1st place finish at a major, there was one achievement left before Leffen could indisputably be considered in the same tier as the "gods": defeating Mew2King, the only one he had not beaten.
This set the stage for Apex 2015, the largest Melee tournament in history at the time, where all five "gods" were present, and where Leffen and Mew2King were seeded to play in winners' quarterfinals. After beating Larry Lurr and aMSa in top 48, Leffen made it to Mew2King. In a momentous 2-1 victory, including a dominant 3-stock on game 3, Leffen defeated Mew2King, becoming the first player to take a tournament set from all five "gods" of Melee. He then went on to face Mango in winners' semifinals; Leffen beat Mango once again, 3-1, to advance to winners' finals and prove that his previous victory was no fluke. Looking poised to take the tournament, Leffen then fell to PPMD 2-3 and Armada 1-3, earning 3rd place. He outplaced three of the five "gods" and cemented himself as one of what was now the "top six," a player able to beat any other Melee player and take major tournaments. As the "Five Gods" is a historical term, the community gave Leffen the title of "Godslayer."
Leffen continued to develop as a top-level threat. At CEO 2015, Leffen earned 1st in singles--his first American national victory. He had a close set with Plup in winners' quarters but ultimately won 2-1, and proceeded to sweep the rest of the tournament, beating Shroomed 3-0 and Armada twice in winners' finals and grand finals; each set was 3-0 and 3-1, respectively. In doubles, Leffen teamed with Hungrybox, placing 2nd; they had managed to trade sets with PewPewU and SFAT and take a set off of Armada and Shroomed, but they ultimately lost a close second set 2-3.
At FC Smash 15XR: Return, Leffen earned 1st in singles. He defeated Swedish Delight 3-0 in winners' quarters, he then beat Hungrybox 3-1 in winners' semis and Armada 3-1 in winners' finals, including a 4-stock in game 1 on Final Destination. In grand finals; he met Hungrybox once again and beat him 3-1.
Leffen once again got first place at WTFox singles, including an impressive 3-0 victory over Mang0's Falco in grand finals, making three consecutive first place finishes in singles. At this point, Leffen looked dominant--a favorite to take future major tournaments.
However, he failed to repeat this success at EVO 2015, being sent into losers by Hungrybox, and then eliminated at 5th place by Plup's Samus.
At Super Smash Con 2015, Leffen bounced back and took first place once again in singles, beating Mew2King 6-1 collectively in winners' finals and grand finals. Mew2King answered back in their next meeting at PAX Prime 2015, where Mew2King took the tournament with a collective 6-0 victory over Leffen.
Leffen once again failed to capture first place at Paragon Los Angeles 2015, being sent to losers by Mew2King, and being eliminated by Hungrybox, ending another tournament run at 5th place.
At HTC Throwdown, Leffen made it to Grand Finals from the winners side, where he defeated Hungrybox in grand finals 3-0.
Leffen's reign of dominance was cut short, however. He was unable to enter The Big House 5, Smash Summit, GENESIS 3, Battle of the Five Gods, and Smash Summit 2 due to international visa issues. Furthermore, he was denied a worker's visa from the United States, primarily for reasons that question Melee's legitimacy as a sport. The video showing the rejection letter started a movement to reverse the decision. Eventually, Leffen came to be temporarily allowed into the USA up until and throughout July 2016, tentatively letting him attend EVO 2016. Due to his visa going through additional processing resulting from his deportation from the US however, Leffen was ultimately unable to attend EVO 2016.
During his American visa issues, he notably won Melee singles at Get On My Level 2016, after beating Mew2King 3-2, Armada 3-1, Hungrybox 3-2, and Mango 3-1 without losing a set.
Leffen's visa was finally accepted on October 3rd, 2016, allowing him to compete in the US again. Since then, he has remained a steady top-level threat, but has not reached the same dominance as in 2015 before his visa issues.
After many years of coming close to the top and failing in the Evolution Championship Series, Leffen finally took 1st place in the Grand Finals of EVO 2018 for Super Smash Bros. Melee.
At Super Smash Con 2019, Leffen took 1st place, notably 6-0'ing Hungrybox.
Post Pandemic Era
After lockdown was over and offline tournaments finally came back, Leffen was perceived to be a Top 3 player in the world, alongside Zain and Mango. In 2021, he attended only 1 tournament in North America: Smash Summit 12. Unfortunately for him, he got 5th place losing to Wizzrobe, iBDW, and Mango. While still a good performance, Leffen was very dissatisfied and was determined to show his true potential in the upcoming Genesis 8 in April 2022.
However, he would not attend that event due to taking care of his new dog. He would attend Pound 2022 the weekend after; as expected, he got to winners semis and was going to face Zain. He opted to go Sheik instead of his usual Fox due to difficulties against Marth. While the set was competitive, he lost 3-1 and later lost to Amsa in loser's quarters for 5th place. Leffen would later have an underperformance at Smash Summit 13 in May 2022, ending at 9th place after losing to Jmook and Llod.
But in June 2022, Leffen would take first place at Battle of BC 4, beating Amsa, Hungrybox, and Zain in two sets. This victory would be his first tournament win in North America since Super Smash Con 2019. Leffen would take a small break before returning to competition in North America in the Fall of 2022, placing 17th at The Big House 10, 3rd at the Ludwig Smash Invitational, and 7th at Smash Summit 14.
Other Smash games
Leffen also played Project M at a high level for a while, and was known as one of the best players of Captain Falcon, Fox, and Zero Suit Samus.
Leffen has occasionally played Smash 4, and notably pioneered the usage of Diddy Kong's up throw to up air combo.
Upon Super Smash Bros. Ultimate's release, Leffen often streamed the game and offered his own opinion on the meta. He was one of the early pioneers of using Pokémon Trainer and has since used the character successfully in tournament. Leffen briefly dropped Pokémon Trainer in favor of Roy and Pichu in April 2019, citing that Pokémon Trainer was not worth the effort, but he would eventually return to the character. Leffen also began labbing Joker upon his release and discovered an infinite lock technique performed by repeatedly using short-hopped up aerials under the opponent while the opponent is on top of a platform. The technique has since been named "Leffoble" in honor of him.
At the end of April, Leffen announced his semi-retirement from Ultimate singles, mainly citing the smaller scene in Sweden and issues with online play making it difficult for him to get any meaningful practice. However, the release of Hero saw his return to the game, and he intended to compete in EVO 2019, but issues with his visa kept him from doing so. Leffen continued to enter for both Melee and Ultimate at major tournaments such as Super Smash Con 2019, and although he put more importance towards Melee, he still found success in Ultimate, with set wins over Tweek, Salem, and other top players. Following his first place at DreamHack Winter 2019, Leffen announced he would once again be putting Ultimate on the backburner, instead focusing on Melee and other fighting games. He has since been critical of the game, which has brought about some controversy.
With Fox, Leffen is known for his consistent execution and movement, and boasts solid fundamentals in all aspects of the game, using a methodical and efficient approach, making him a very well-rounded player. Leffen has both a great neutral game, as he rarely overextends or overreaches in games even against weaker opponents, and a solid combo game, especially against fastfallers. He is renowned for his proficiency against Falco, Peach, and other Foxes, having made his first upsets against the Five Gods in those matchups. Leffen's prowess against Peach is so great that even Armada, the best Peach in the world, would primarily opt for the Fox ditto in tournament instead, generally only playing Peach on Final Destination. He is also arguably the best Fox player in the world at edgeguarding, which heavily contributes to his success in the Fox ditto and several other matchups.
While Leffen is well-rounded, he undoubtedly focuses on the mental game and adaptation more than technical play. Leffen has once stated in an interview that he believes many high-level players are held back by "flowchart" behavior that he is able to exploit. This is clearly exemplified by his ability to "clutch" out sets from losing positions, even from 0-2 deficits. Despite this, he still puts in the work to lab certain matchups or situations that give him trouble, showing his solid work ethic; he's even known to lab other miscellaneous characters solely to push the metagame forward. Along with Armada, he practices with Snowy for the Jigglypuff matchup, and has flown him out to events such as Summit in order to prepare for facing Hungrybox in bracket.
Prior to his establishment as a top 5 player, Leffen had noticeable trouble against punish-heavy players. Despite his strong fundamentals, he struggled if his opponent could overwhelm him technically, leading to losses against Silent Wolf, Westballz, and Javi, among others. He also could not defeat Mew2King for a long time, even after he had upset the rest of the Five Gods, because of that aforementioned weakness. Leffen was also noted to be fairly poor at the Samus matchup, having, at one point, losing records with HugS and Duck, both of whom are considered far below his skill level. He has also lost three times to Plup in solo Samus sets. However, he has since overcome these weaknesses and no longer drops sets as frequently to these types of players, most notably not having lost to solo Samus since 2018.
Super Smash Bros. Melee
|Tournament||Date||1v1 Placement||2v2 Placement||Partner||Earnings|
|STIIG||July 13th-20th, 2010||9th||4th||AJP|
|SKN2||October 8th-10th, 2010||7th||7th||AJP|
|B.E.A.S.T||January 7th-9th, 2011||9th||13th||AJP|
|SKN3||February 11th-13th, 2011||3rd||3rd||AJP|
|Beauty||April 15th-17th, 2011||3rd||5th||AJP|
|Tampora 2||April 29th-May 1st, 2011||2nd||3rd||AJP||$195|
|Beauty 2||May 2nd-5th, 2011||2nd||2nd||AJP|
|GENESIS 2||July 15th-17th, 2011||17th||13th||AJP|
|B.E.A.S.T II||August 10th-14th, 2011||4th||5th||AJP||$86.24|
|Tampora 3||November 25th-27th, 2011||4th||3rd||Zoler||$6.67|
|Beauty 3||December 2nd-4th, 2011||2nd||2nd||Zoler|
|Apex 2012||January 6th-8th, 2012||33rd||25th||Zoler|
|Gamers Meetup STHLM||February 18th-19th, 2012||2nd||1st||Fuzzyness|
|Epita Smash Arena 5||April 20th-23rd, 2012||5th||2nd||Fuzzyness|
|Haags Kwartiertje 6||June 16th, 2012||4th||4th||Beat|
|Smashers' Reunion: Melee Grande||July 13th-15th, 2012||3rd||2nd||Dr. PeePee||$369|
|King Funk's Castle II: Måske||October 4th-7th, 2012||3rd||2nd||Ice|
|hf.lan 4||December 1st-2nd, 2012||2nd||3rd||NMW||$188.12|
|Apex 2013||January 11th-13th, 2013||17th||5th||Ice|
|EVO 2013||July 12th-14th, 2013||9th||5th||Ice|
|CFST: WarZone 2||September 1st, 2013||7th||2nd||MattDotZeb|
|hf.lan 6||December 14th-15th, 2013||2nd||1st||Ice||$220.02|
|Apex 2014||January 17th-19th, 2014||4th||9th||Dr. PeePee||$628|
|B.E.A.S.T 4||February 12th-16th, 2014||1st||2nd||Ice||$1,239.03|
|Republic of Fighters 3||May 17th-18th, 2014||1st||2nd||Fuzzyness||$1,314|
|MLG Anaheim 2014||June 20th-22nd, 2014||5th||5th||Hax||$1,000|
|EVO 2014||July 11th-13th, 2014||9th||3rd||Ice|
|COMEBACK I||August 1st-3rd, 2014||2nd||1st||Beat||$156.66|
|Hit & Stun Tournament 2||September 6th-7th, 2014||3rd||2nd||Ice|
|Beauty 8||September 12th-14th, 2014||2nd||1st||Professor Pro|
|The Big House 4||October 4th-5th, 2014||3rd||3rd||Hax||$855|
|Smashsätra||October 11th, 2014||1st||—||—|
|DrømmeLAN 4.0||November 7th-9th, 2014||2nd||2nd||Ice|
|hf.lan 8||November 22nd-23rd, 2014||1st||1st||Ice|
|Beauty 9||December 5th-7th, 2014||2nd||2nd||Pop||$138|
|B.E.A.S.T 5||January 9th-11th, 2015||1st||2nd||Ice||$2,971|
|Paragon Orlando 2015||January 17th-18th, 2015||3rd||3rd||MacD||$542|
|Apex 2015||January 30th-February 1st, 2015||3rd||3rd||Ice||$2,711|
|Cannes Winter Clash||February 27th-March 1st, 2015||1st||—||—||$407.86|
|NeoNebulous 7||March 28th, 2015||1st||1st||G$|
|Beauty 10||April 2nd-6th, 2015||2nd||2nd||Professor Pro||$173|
|I'm Not Yelling!||April 11th-12th, 2015||3rd||1st||MacD||$593|
|MVG Sandstorm||April 18th-19th, 2015||5th||1st||MacD||$173|
|DrømmeLAN 4.5||April 24th-26th, 2015||2nd||2nd||Fuzzyness|
|Press Start||May 9th-10th, 2015||9th||2nd||MacD|
|Headstomper '15||May 16th, 2015||1st||1st||King Funk|
|Battle Arena Melbourne 7||May 22nd-24th, 2015||2nd||1st||Blue2ez||$737.27|
|CEO 2015||June 26th-28th, 2015||1st||2nd||Hungrybox||$4,698|
|FC Smash 15XR: Return||July 4th-5th, 2015||1st||—||—||$852|
|WTFox||July 10th-11th, 2015||1st||2nd||Mango||$1,525|
|EVO 2015||July 17th-19th, 2015||5th||—||—||$373|
|Super Smash Con||August 6th-9th, 2015||1st||1st||MacD||$5,749|
|Heir II the Throne||August 14th-16th, 2015||5th||2nd||Ice|
|PAX Prime 2015||August 28th-30th, 2015||2nd||1st||MacD||$875|
|Paragon Los Angeles 2015||September 5th-6th, 2015||5th||—||—||$373|
|HTC Throwdown||September 19th, 2015||1st||2nd||MacD||$5,648|
|The Call of Ragnarok||September 26th-27th, 2015||1st||—||—|
|Eclipse||November 14th-15th, 2015||2nd||2nd||Ice||$1,973|
|DreamHack Winter 2015||November 26th-29th, 2015||9th||5th||Ice|
|Kickstart 5||January 24th, 2016||1st||2nd||Professor Pro|
|B.E.A.S.T 6||February 19th-21st, 2016||2nd||1st||Ice||$1,047.77|
|Webhallen Fridhemsplan 3/5||March 5th, 2016||1st||—||—|
|Kickstart 7||March 13th, 2016||1st||1st||Lamp|
|HFLAN 12||April 9th-10th, 2016||1st||2nd||BrTarolg|
|The Come Up 2016||April 23rd-24th, 2016||1st||—||—||$311.22|
|Enthusiast Gaming Live Expo||April 29th-May 1st, 2016||7th||2nd||Hungrybox||$120|
|Battle of BC||May 14th, 2016||1st||—||—||$989|
|Get On My Level 2016||May 20th-22nd, 2016||1st||3rd||Hungrybox||$3,078|
|Headstomper '16||June 4th-5th, 2016||1st||–||–|
|DreamHack Summer 2016||June 18th-21st, 2016||1st||—||—||$4,700|
|Stockholm Monthly 6/28||June 28th, 2016||1st||—||—|
|Stockholm Weekly 8/8||August 8th, 2016||1st||—||—|
|Stockholm Weekly 9/13||September 13th, 2016||1st||—||—|
|Heir 3||August 19th-21st, 2016||7th||33rd (DQ)||Yabasta||$123|
|The Big House 6||October 7th-9th, 2016||17th||—||—|
|Stockholm Monthly 10/4||October 4th, 2016||1st||—||—|
|Stockholm Weekly 10/18||October 18th, 2016||1st||—||—|
|Eclipse 2||October 21st-23rd, 2016||3rd||2nd||Ice|
|Stockholm Monthly 10/25||October 25th, 2016||1st||—||—|
|Smash Summit 3||November 3rd-6th, 2016||9th||3rd||Mafia||$432|
|DreamHack Winter 2016||November 24th-27th, 2016||3rd||—||—||$3,000|
|UGC Smash Open||December 2nd-4th, 2016||4th||2nd||Ice||$1,241|
|Don't Park on the Grass||December 17th-18th, 2016||1st||2nd||Ice||$2,960|
|GENESIS 4||January 20th-22nd, 2017||5th||2nd||Ice||$511|
|LanETS 2017||February 11th-12th, 2017||1st||1st||KirbyKaze|
|B.E.A.S.T 7||February 17th-19th, 2017||2nd||2nd||Ice||$1,003.92|
|Smash Summit Spring 2017||March 2nd-5th, 2017||3rd||2nd||Ice||$6,430|
|Full Bloom 3||March 25th, 2017||9th||5th||Ice|
|Capital of Smash 2||April 8th, 2017||1st||—||—|
|DreamHack Austin 2017||April 28th-30th, 2017||7th||—||—||$300|
|Royal Flush||May 12th-14th, 2017||5th||2nd||Ice||$415|
|Smash 'N' Splash 3||June 2nd-4th, 2017||2nd||—||—||$2,696|
|DreamHack Summer 2017||June 17th-18th, 2017||2nd||—||—||$2,000|
|Smash @ Power 9 #39||July 6th, 2017||1st||—||—|
|GENESIS: RED||July 9th, 2017||—||1st||Ice|
|EVO 2017||July 14th-16th, 2017||9th||—||—|
|FUSE||July 16th, 2017||—||7th||Ice|
|Get On My Level 2017||July 30th, 2017||1st||1st||Ice||$1,820|
|Super Smash Con 2017||August 10th-13th, 2017||9th||—||—||$54|
|Heir 4||August 17th-21st, 2017||1st||—||—||$2,450|
|Shine 2017||August 25th-27th, 2017||5th||3rd||Ice|
|Uppsala Weekly 9/18||September 18th, 2017||1st||—||—|
|GameTyrant Expo 2017||September 29th-October 1st, 2017||13th||—||—||$300|
|The Big House 7||October 6th-8th, 2017||3rd||—||—||$1,826.40|
|Canada Cup 2017||October 28th-30th, 2017||2nd||1st||Mew2King|
|Smash Summit 5||November 2nd-5th, 2017||3rd||1st||Armada||$10,469.75|
|DreamHack Winter 2017||December 2nd-3rd, 2017||3rd||—||—||$1,000|
|Valhalla||January 4th-8th, 2018||1st||—||—|
|GENESIS 5||January 19th-21st, 2018||3rd||—||—||$1,225|
|Phoenix Blue||February 22nd-24th, 2018||2nd||—||—|
|The Mango||March 18th, 2018||13th||—||—|
|Full Bloom 4||March 24th-25th, 2018||3rd||—||—||$651|
|Ventus||April 14th, 2018||1st||1st||Beat||$118|
|Flatiron 3||April 21st, 2018||1st||—||—|
|Smash Summit 6||May 3rd-6th, 2018||5th||1st||Armada||$990.45|
|King of Nordic: Super Smash Bros. Melee @ Birdie||May 10th-13th, 2018||1st||1st||Beat|
|Smash 'N' Splash 4||June 1st-3rd, 2018||3rd||—||—||$2,136|
|Low Tier City 6||July 27th-29th, 2018||2nd||—||—|
|EVO 2018||August 3rd-5th, 2018||1st||—||—||$8,118|
|Super Smash Con 2018||August 10th-13th, 2018||65th (DQ)||—||—|
|Heir 5||August 17th-19th, 2018||1st||—||—|
|The Big House 8||October 5th-7th, 2018||5th||—||—||$516|
|Red Bull EWKND||November 1st-3rd, 2018||1st||—||—||$269.29|
|The Mang0: Homecoming||November 10th-11th, 2018||1st||—||—||$1,750|
|Smash Summit 7||November 15th-18th, 2018||2nd||5th||Mango||$8,927|
|DreamHack Winter 2018||December 1st-2nd, 2018||1st||—||—||$2,700|
|GENESIS 6||February 1st-3rd, 2019||129th (DQ)||—||—|
|Get On My Level 2019||May 17th-19th, 2019||3rd||—||—||$702.04|
|Smash 'N' Splash 5||May 31st-June 2nd, 2019||3rd||—||—|
|Smash Summit 8||June 13th-16th, 2019||3rd||—||—||$3,472|
|Super Smash Con 2019||August 8th-11th, 2019||1st||—||—||$3,838|
|Shine 2019||August 23rd-25th, 2019||5th||—||—||$330|
|The Big House 9||October 4th-6th, 2019||3rd||—||—||$1,090|
|Valhalla III||January 9th-13th, 2020||1st||—||—|
|GENESIS 7||January 24th-26th, 2020||5th||—||—||$118|
|Smash Summit 9||February 13th-16th, 2020||9th||—||—||$1,387|
|Battle of the Armada - Melee Edition 2||August 15th, 2020||1st||—||—||$355|
|Poilon Arena 3||November 12th, 2020||1st||—||—|
|Smash Summit 10 Online Europe||November 19th-22nd, 2020||1st||—||—||$1,200|
|Schweeklies #4||January 14th, 2021||1st||—||—|
|Valhalla Online||January 30th-31st, 2021||2nd||—||—|
|Eurat.gg Melee Series #1||February 6th, 2021||3rd||—||—||$120|
|Saturday Night LEVO #6 Europe||February 13th, 2021||1st||—||—|
|The Upset||February 27th-28th, 2021||1st||—||—||$132|
|Saturday Night LEVO #9 Europe||March 13th, 2021||1st||—||—|
|Poilon Colosseum||May 8th-9th, 2021||1st||—||—||$973|
|SWT: Europe Melee Regional Finals||October 23rd-24th, 2021||1st||—||—||$1,600|
|Smash Summit 12||December 9th-12th, 2021||5th||—||—|
|Pound 2022||April 22nd-24th, 2022||5th||—||—|
|Smash Summit 13||May 12th-15th, 2022||9th||—||—|
|Battle of BC 4||June 10th-12th, 2022||1st||—||—|
|The Big House 10||October 7th-9th, 2022||17th||—||—|
|DreamHack Rotterdam 2022||October 14th-16th, 2022||1st||—||—||$1,350.28|
|Ludwig Smash Invitational||October 21st-23rd, 2022||3rd||—||—||$5,250|
|Smash Summit 14||November 3rd-6th, 2022||7th||—||—||$1,593|
|Mainstage 2022||December 2nd-4th, 2022||5th||—||—|
|Scuffed World Tour||December 18th, 2022||5th||—||—|
|GENESIS 9||January 20th-22nd, 2023||7th||—||—||$375.90|
|Smash @ SPACE 2||February 28th, 2023||1st||—||—|
|Battle of BC 5||May 19th-21st, 2023||5th||—||—||$306|
|Tournament||Date||1v1 Placement||2v2 Placement||Partner|
|GENESIS 2||July 15th-17th, 2011||3rd||—||—|
|King Funk's Castle II: Måske||October 4th-7th, 2012||2nd||1st||Fuzzyness|
|Apex 2014||January 17th-19th, 2014||9th||—||—|
|B.E.A.S.T 4||February 12th-16th, 2014||3rd||—||—|
|COMEBACK I||August 1st-3rd, 2014||2nd||—||—|
|Hit & Stun Tournament 2||September 6th-7th, 2014||2nd||—||—|
|Beauty 8||September 12th-14th, 2014||3rd||—||—|
|The Big House 4||October 4th-5th, 2014||33rd||—||—|
|DrømmeLAN 4.0||November 7th-9th, 2014||2nd||—||—|
|hf.lan 8||November 22nd-23rd, 2014||1st||—||—|
|B.E.A.S.T 5||January 9th-11th, 2015||4th||—||—|
|Beauty 10||April 2nd-6th, 2015||1st||—||—|
|DrømmeLAN 4.5 All-Star||April 24th-26th, 2015||1st||—||—|
|Paragon Los Angeles 2015||September 5th-6th, 2015||49th (DQ)||17th||Professor Pro|
Super Smash Bros. for Nintendo 3DS
|Tournament||Date||1v1 placement||2v2 placement||Partner|
|DrømmeLAN 4.0||November 7th-9th, 2014||1st||—||—|
Super Smash Bros. for Wii U
|Tournament||Date||1v1 placement||2v2 placement||Partner|
|Beauty 9||December 5th-7th, 2014||1st||—||—|
|B.E.A.S.T 5||January 9th-11th, 2015||3rd||—||—|
|Paragon Orlando 2015||January 17th-18th, 2015||9th||—||—|
|DrømmeLAN 4.5||April 24th-26th, 2015||1st||—||—|
Super Smash Bros. Ultimate
|Tournament||Date||1v1 placement||2v2 placement||Partner|
|Valhalla II||January 3rd-7th 2019||7th||—||—|
|GENESIS 6||February 1st-3rd, 2019||17th||—||—|
|Ultimate Nimbus||March 3rd, 2019||9th||—||—|
|Smash Ultimate Summit||March 8th-10th, 2019||9th||—||—|
|2GG: Prime Saga||April 13th-14th, 2019||49th||—||—|
|Mega Smash Mondays 185||April 15th, 2019||13th||—||—|
|Pound 2019||April 19th-21st, 2019||13th||—||—|
|Get On My Level 2019||May 17th-19th, 2019||257th (DQ)||—||—|
|Super Smash Con 2019||August 8th-11th, 2019||17th||—||—|
|Shine 2019||August 23rd-25th, 2019||33rd||—||—|
|Mainstage||September 20th-22nd, 2019||17th||—||—|
|Smash Ultimate Summit 2||October 24th-27th, 2019||9th||—||—|
|DreamHack Winter 2019||November 29th-December 2nd, 2019||1st||—||—|
Despite being considered one of the best professional smashers in Melee, Leffen has led a controversial career as a smasher, due to his previously rude conduct during and outside of tournaments. Several players, most of which were new smashers to the scene, accused him of:
- deliberately sandbagging in pools by playing low tier characters while insulting his opponent's skill throughout and after the match.
- spreading exaggerated rumors about others, making rude and provocative comments on SmashBoards, and deliberately starting arguments with users.
- further blaming other people when confronted about his actions, using his status as a top professional player to decrease his punishments.
After noticing his poor behavior, Swedish tournament organizers and other Melee professionals of his caliber gave him repeated warnings concerning his attitude. In August 2012, Leffen was eventually threatened with a ban from tournaments if he did not improve his attitude, but he did not take the claim seriously. This led to further discussions among the European Smash community that culminated in his national ban from Swedish tournaments, effective February 9th, 2013.
The discussion group announcing his ban compiled a significant amount of evidence of his poor behavior into a downloadable archive, and demanded that Leffen create a lengthy apology about all of his wrongdoings and how he would change his behavior in the future, should he return to the community. On March 21st, 2013, Leffen made his public statement asking for forgiveness; despite this, he was not immediately unbanned, and ended up missing almost one year's worth of local tournaments. On January 24th, 2014, it was announced by Armada that the Swedish ban on Leffen was no longer in place . His conduct since then has improved dramatically, but he still remains a relatively controversial figure in the community, especially on social media sites such as Reddit and Twitter, due to his blunt comments.
At Heir II the Throne, Leffen was banned from commentary on all future European Smash Circuit events for saying that it wasn't a "serious" tournament and players were playing their secondaries and not trying. Leffen notably compared the tournament to The Foundry, a series notorious for its relaxed and non-competitive atmosphere. Many argued that the TOs had overreacted in their decision, and that a full ban was an excessively harsh punishment.
During top 8 of Shine 2017, ChuDat narrowly beat Leffen 3-2 getting a reverse 3-0 on him, ending Leffen's run at 7th. It was later discovered that the set had been played on vanilla Melee instead of with UCF enabled, a mod designed to make shield dropping and dash back consistent rather than RNG based. The set would be controversially replayed, resulting in a 2-3 victory for Leffen, ending ChuDat's run at 7th. Leffen would receive backlash from this, although the decision had been made by the Shine TOs; many agreed that Leffen should not have received such negative attention for the ruling, as the TOs had created the situation by failing to check that UCF was turned on.
Opinion on Ultimate
Despite focusing on Ultimate for a year, Leffen has been openly critical about the game, even going as far as to say that playing top-level Ultimate "is just pure fucking torture to me." As a result, he has butted heads with several other Ultimate professionals. Most notably, on September 26th, 2020, he argued with Rickles that streaming Ultimate was painful to him, that he would "rather flip burgers at [sic] mcdonalds if it paid the same amount," and that streaming Ultimate was harder than holding a minimum wage job. This Tweet was met with backlash and mockery from the community: users noted the difficulty of minimum wage jobs especially during the COVID-19 pandemic while several Smashers such as Axe recounted how they hated working at their minimum wage jobs before they went professional. The Tweet eventually caused "Leffen" to trend on Twitter. Leffen would later delete and apologize for his minimum wage Tweet.
On July 2nd, 2020, amidst a wave of sexual harassment allegations in the community, artist Jisu posted a tweet where she called out ZeRo for showing her hentai and explicit Craigslist ads when she was 15. ZeRo later responded, admitting that he looked at hentai but denied that he had shown it to her, nor would he show it to an entire room of people. He also denied showing her the ads. Following this defense, many people started to target Jisu for "clout-chasing." Leffen however would defend Jisu's claims by claiming that he saw ZeRo show people hentai in public, a statement that was backed up by a screenshot from an anonymous user later sent to Leffen. ZeRo would later confirm this and many other allegations made about him to be true several days later. 
However, on June 25th 2021, Technicals would make a YouTube video where he challenged a vast majority of Jisu's allegations towards ZeRo. In the same video, Technicals featured a brief section where he interviewed ZeRo about Leffen's allegations. ZeRo stated that he didn't remember any of the events that Leffen claimed to have happened. He would later state in the interview that he felt as if "he was trapped by Leffen into being pressured into admitting the truth" due to all of the allegations against him, and that by apologizing for Leffen and Katie, he would be creating a false agenda that Jisu's story would be correct. Both Leffen and Jisu have yet to respond to Technical's and ZeRo's allegations.
- Leffen was commonly considered a villain in the Smash community due to his reportedly rude behavior and trash-talk. He claimed that he enjoyed his given title due to the community's need of someone to root against, although a controversy existed over whether he should embrace it or not.
- Leffen has also been compared to Gary Oak from the Pokémon anime due to their similar personality and appearance. Additionally, Leffen mains Pokémon Trainer in Ultimate.
- Leffen is the subject of the two-season Red Bull documentary Cultivation Leffen: Resurrection, which chronicles the time period from his initial ban through his visa issues and his triumph at Get On My Level 2016.
- At Apex 2015's Salty Suite exhibition, Leffen won a $100 money match 5-0 against Chillin in Fox dittos; Chillin was also forbidden from using Fox's default costume in future tournaments. However, at The Big House 6, Leffen allowed Chillin to use the costume again.
- After Leffen won EVO 2018, Chillin humorously tweeted out that "Leffen confirmed no longer has to show his elders some respect".
- After Chillin suffered from a stroke in June 2022, Leffen used Fox's blue costume at Battle of BC 4 while spreading awareness of a GoFundMe campaign created to alleviate Chillin's medical costs.
- Leffen has gotten into scuffles with Salem on Twitter, originating in December of 2018, with the two taking shots at each other on Twitter, with Salem mocking Leffen's skill at Ultimate.
- The two were scheduled to meet in bracket at multiple tournaments but never did due to upsets and DQs. They finally met in bracket at Super Smash Con 2019, where Leffen beat Salem 2-1.
- Leffen's lifetime set count against Mew2King (9-17) is his worst set count against a god (excluding PPMD).
- Leffen is infamous for a spate of losses against Samus players HugS, Plup, and Duck in 2015 and 2016 after having mocked Chillin's losses to the same character on Twitter.
- He is the first person to four-stock Armada in bracket, doing it twice at FC Smash 15XR: Return and at Smash 'N' Splash 4.
- Leffen, along with Tafokints and Zomba, holds the title of the most money won in a single money match. He won $1,000 on three different occasions :
- At Apex 2015, Leffen and Mango's Winners Semis set was also a $1,000 money match. The Swedish player won the set 3-1.
- At DreamHack Winter 2015, Leffen defeated SFAT 5-1 in a $1,000 money match.
- At The Kid, the Goat, the Mang0, Leffen and Mango bet $1,000 on a loser's quarter-finals match between Lucky and Swedish Delight, with Leffen betting on Swedish, and Mango voting on Lucky. Swedish Delight would go on to win the set.
- Leffen is sometimes referred to by his nicknames Yung Leff or Big Leff. Depending on how he plays and if he wins or loses, the adjective used can vary (Humoungous Leff, Massive Leff when winning, Small Leff, Minuscule Leff when losing). He has also been referred to these names by Dragon Ball FighterZ commentators.
- Leffen is Korean-Swedish, as his father was adopted from South Korea and his mother is Swedish. Leffen stated that his family doesn't follow Korean cultural traditions.
- Outside of Smash, Leffen formerly was a professional Dragon Ball FighterZ player, being one of the best DBFZ players in Europe, and is currently ranked 28th on the Panda Global Rankings Z. He frequently streams Dragon Ball FighterZ and entered multiple DBFZ tournaments, placing very well. He has retired from competing in the game, citing Toei’s meddling in tournaments, and Arc System Works's way of patching as the two reasons he does not enjoy the game anymore.
- Leffen is currently the only Smash player to have been invited to a non-Smash-related Summit event (Summit of Power).
- Leffen is also a professional Guilty Gear: Strive player, being one of the best players in the world and placing 3rd at EVO 2022.
- Leffen is the subject of a popular Twitter parody account known as the Deep Leffen Bot, a natural AI learning model created by a PhD student that is trained on Leffen's tweets, various Smash subreddits, and other "unsavory source materials". The bot is popular in the Smash community for its humorous and creative content output. Although he initially blocked the bot's account on Twitter, Leffen has since come around and praised the bot for its artistic and comedic value.
- Leffen has an extremely proficient Mewtwo secondary, reaching the top of the ranked European Project Slippi leaderboards (and taking offline sets locally against top European players) under the alias of MewTwoMan.
- ^ Leffen's first Ultimate retirement.
- ^ Leffen's Tweet before DreamHack Winter 2019.
- ^ Flipping Burgers Tweet.
- ^ Archived Minimum Wage Tweet.
- ^ Leffen apologizing for his Tweet.
- ^ Jisu's statement.
- ^ ZeRo's response to Jisu.
- ^ https://www.twitlonger.com/show/n_1sra9ee?new_post=true.
- ^ ZeRo's final statement.
- ^ Technicals' video.
- ^ Leffen's endorsement of Deep Leffen.
- Swedish smashers
- Fox players (SSBM)
- Falco players (SSBM)
- Yoshi players (SSBM)
- Mewtwo players (SSBM)
- Sheik players (SSBM)
- Diddy Kong players (SSB4)
- Captain Falcon players (PM)
- Fox players (PM)
- Zero Suit Samus players (PM)
- Mewtwo players (PM)
- Pokémon Trainer players (SSBU)
- Pichu players (SSBU)
- Roy players (SSBU)
- Arcade controller players
- VIP players