Greatest of all time
Greatest of all time, often shortened to GOAT, is an informal title used by a fanbase to label a person considered the best ever to compete or participate in a particular field. The term is most widely used in professional sports; for example, most basketball players and fans consider either Michael Jordan or LeBron James. It is also used in other competitive fields such as chess or video gaming; Faker is widely seen as the greatest League of Legends player of all time.
The Super Smash Bros. series has been played competitively since 2002 (as early as 1999 in its native Japan), and as the tournament scene has continued to develop, the communities for each game in the series have formed a consensus around one, or several, candidates considered the "greatest of all time" for their particular title.
Common criteria used to judge the greatest of all time include:
In Super Smash Bros. 64
Isai is widely considered to be the greatest Smash 64 player of all time.  This is due to his extended longevity as a competitor and dominance over the Smash 64 scene across all regions of the world (most famously showcased during his trip to Japan in 2006-2007).
In Super Smash Bros. Melee
Super Smash Bros. Melee is perhaps the only Smash title with significant debate regarding its greatest player of all time.
Most Melee players, commentators, and supporters consider Armada to be the greatest Melee player of all time, due to his consistent level of dominance over all other competitors during his prime. Among Armada's major accomplishments include first place finishes at some of the most prestigious Melee supermajors. He won EVO 2015 and EVO 2017, won three GENESIS titles, two Apex titles, and four Smash Summit in a row.
Armada holds positive set records against all of the other Gods. He was considered a candidate for best player in the world from 2009 until his retirement from Melee in 2018. Armada was commonly considered to be the best player in the word in 2011 and 2012, and in the first six editions of SSBMRank, he was ranked 1st in 2015 and 2016. Additionally, he was ranked 2nd in 2013, 2014, 2017, and 2018, meaning that Armada has never fallen below 2nd place since 2011.
Supporters of Armada also point to his unrivaled level of consistency as a competitor; unlike the other Gods, who were known for occasionally losing to lower-ranked players, Armada was known for almost never dropping to a set to players below his skill level. From 2009 to 2018, he never placed below 5th at a major, and lost only three sets to players ranked below the top six: two best of three sets to SilentSpectre and Swedish Delight, and one best of five sets to Amsah. Armada was known as a major roadblock in the path of many players' goals to achieve victory over all five of the Gods, including Axe and Wobbles. Armada achieved much of his dominance using almost entirely Peach, a character considered less viable than other top tiers such as Fox, and also while hailing from Sweden, in a continent with fewer major tournaments and far weaker competition than North America.
A smaller but significant share of the Melee community argues that Mango is the greatest Melee player of all time. His major accomplishments include first place finishes at EVO 2013 and EVO 2014, matching Armada's record of EVO victories, along with wins at Pound 3, GENESIS, The Big House 4, and Get On My Level 2019.
Mango was considered a top-ten player in 2007, and has since remained as a top five player from 2008 to the present, aside from a period in 2010-2011 where he sandbagged as Scorpion Master. He was considered one of the two best players in the world in 2008, and the undisputed best player in the world from 2009-2010 and 2013-2014. He was ranked 1st on the 2013 and 2014 SSBMRank.
Supporters of Mango cite his greater longevity compared to Armada with his peaks being just as dominant, if not greater than, Armada's (for example, winning back-to-back EVOs which no other player has done), They also argue that he was able to achieve number one in the world using three different characters (Jigglypuff, Falco, and Fox), all with different playstyles. Mango is often seen as the most influential and recognizable Melee player, as he popularized a highly aggressive and read-based style of play with his space animals, which made him a fan favorite at tournaments, and he boasts the largest Twitch following out of any Melee player; he is often regarded as the "protagonist" of Melee., Mango is commonly nicknamed "the GOAT" or "ManGOAT," even by players who consider Armada the greatest of all time.
Both Armada and Mango have publicly commented on the GOAT debate. Armada has referred to himself as the GOAT on Twitter multiple times since 2018. In October 2020, Armada and Mango both replied to a Tweet posted by Tafokints discussing the GOAT of Melee. Armada replied to the Tweet first, arguing in favor of his GOAT status, citing his winning record over the rest of the top six, better placements at events the two both attended and having never placed below 5th at any tournament. Mango argued that Armada was only ranked number one for two years (2015 and 2016), and even then, Mango boasted a winning record over him in 2016. He argued that his performance was superior to Armada's before 2012 and that his consistent performance did not necessarily translate into dominance, suggesting that he could have been declared the undisputed GOAT if he chose to retire in 2015. He also added, "At the end of the day it's dumb to discuss whos the goat when we're only halfway thru the movie... There's so much more melee to be played."
Smaller groups have also suggested Ken, Mew2King, and Hungrybox as possible outlier candidates. Ken, known today by his nickname "The King of Smash", is considered the undisputed best player of the MLG era before Brawl's release, and was a candidate for best player in the world from 2004 to 2007. During his prime, Ken was considered the best player by a significant margin, winning nearly every event he entered, and dominated competitive Melee to a degree far greater than Armada or Mango did during their peaks. However, it is generally agreed that Ken's short longevity at the top diminishes his claim at the GOAT. It has been suggested that Ken competed in a less advanced era of Melee, and that the overall level of competition has greatly improved since his retirement, as evidence by his failure to place top eight at majors during his return to Smash from 2013-2015.
Mew2King has spent more time than any other player at the top of competition. He has been considered a top 6 player in the world for 13 years straight, longer than anyone else, from 2006 all the way to 2018, while arguably being top 10 in 2019. In 2007, Mew2King was widely considered the best Melee player in the world, being the only player that year to win more than one major tournament. Mew2King has also remained as a contender to win major tournaments in the following years, winning several major tournaments in 2013-2014, and 2016-2018, including The Big House 3, Shine 2016, and Smash Summit 6. He has largely been credited for advancing the Marth and Sheik metagame to where they nowadays, being the best Marth player in the world from 2007-2013 and 2015-2018, and the best Sheik player from 2008-2017. However, Mew2King has since failed to replicate his success since 2007, as after getting challenged by Mango for the #1 spot in 2008, Mew2King has never been considered top 2 in the world since, peaking at #3 on the 2013 SSBMrank. He has also spent the shortest time out of everyone as the best player in the world, only from 2007 to arguably 2008.
Hungrybox has been considered a top-five player from 2009 until the present and was seen as the undisputed rank one from 2017 to 2019. Among his major titles is a victory at EVO 2016, the largest Melee tournament of all time. His Jigglypuff has been responsible for major developments in the Melee metagame; his dominance caused many to start seeing Jigglypuff as potentially the best character in the game, and many players, most notably Armada, developed secondary characters specifically in an attempt to counter him. However, Hungrybox's reign as a consistent first-place finisher has been relatively short compared to that of Mango or Armada, and his lowest level of play has also been below them; most notably from Apex 2010 to Paragon Orlando 2015, he went nearly five years without placing 1st at a major title. It is often theorized that Hungrybox could become the greatest of all time if he continues to dominate the Melee scene after several more years of competition.
"The Top 100 Melee Players of All Time"
"The Top 100 Melee Players of All Time" is a project by Smash History creators Edwin Budding and Pikachu942, which subjectively ranks the 100 greatest Melee players throughout the history of the game. The first edition, published in 2018, ranked Armada as the greatest player of all time, with Mango in second, Ken in third, and Hungrybox in fourth. A 2019 update moved Hungrybox up to third, ahead of Ken. The ranking was again updated in 2020, and Hungrybox was again moved up to second, ahead of Mango.
"Top 100 Melee Players of All Time" ranked the top 100 Melee players from 2002 to 2018.
Released on February 14th, 2019, this update was titled "All-Time Melee Top 100: Another Year". This update to the Top 50 accounts for every major that occurred since the original list up to GENESIS 6.
Released on March 31st, 2020, this update was titled "All-Time Melee Top 100: Another Year". This update to the Top 50 accounts for every major that occurred since the previous list up to Smash Summit 9.
In Super Smash Bros. Brawl
Mew2King was widely considered to be the greatest Brawl player of all time. Mew2King was by far the most dominant player from 2008-2011, placing first or second at nearly every event he attended. Although his tournament results slumped from 2012 to 2014, he was still considered a threat to win any major tournament, and few other players were able to match his earlier levels of dominance at that time. Many of Brawl's most memorable sets featured Mew2King being upset by other players, including vs. Ally, OCEAN, and Salem.
In Super Smash Bros. 4
ZeRo was widely considered to be the greatest Smash 4 player of all time. From 2014 to 2017, ZeRo placed first at nearly every tournament he entered, including a 56-tournament winning streak from 2014 to 2015. Taking a set off of ZeRo was often considered one of the highlights of a Smash 4 player's career. Although ZeRo retired from entering Smash 4 tournaments in 2018, no other player was about to match ZeRo's level of dominance and consistency before the end of the game's competitive life, leaving his claim as the Smash 4 GOAT undisputed.
In Super Smash Bros. Ultimate
While the game is only two years old, MkLeo has dominated the competitive scene for its entire lifespan, placing 1st at most of the game's significant tournaments. Widely regarded as the game's strongest player offline, his results have suffered somewhat since the switch to online play due to the COVID-19 pandemic. Nonetheless, his perception as Ultimate's top offline player remains unchanged as the competitive community awaits the return of in-person tournaments.
In Project M
ThundeRzReiGN is generally considered to be the greatest Project M player of all time, due to both his dominance and consistent level of play, placing first at nearly every tournament he entered from 2016 to 2019.
Across all Smash games
Mew2King is often considered the greatest player across all Smash titles. Mew2King is recognized as the greatest Brawl player of all time, a consistent top-five Melee player (considered best in the world in 2007), and a strong Project M and Smash 4 player, having placed top eight at many major tournaments, while also entering Smash 64 and Ultimate events. Mew2King is well known for his enjoyment of every Smash title and is one of the only top players who has spent their career competing in multiple games at once; since 2008, he has simultaneously played Melee and the newest Smash game at the time (Brawl from 2008-2014, Smash 4 from 2014-2018, Ultimate since 2018) (in addition to Project M from 2014-2015). Mew2King is also perhaps the most recognized player across the entire competitive Super Smash Bros. scene.
The tournament series Super Smash Con has run an exhibition event called "Smash Masters", in which players compete against each other across all official Smash titles, in an attempt to determine the best overall Smash player. Mew2King won Smash Masters in 2016 and 2018, Wizzrobe won in 2017, and ZeRo won in 2019.