X10, formally known as X Series X and codenamed Satori, was the tenth tournament in the X Tournament Series. The tournament was organized and operated on 26 September 2015 by Doqtor Kirby. X10's entrant count was hindered because of the discontinuation of the Super Smash Flash 2 IRC Chat, due to Doqtor Kirby closing its doors a couple of days prior. X10 also marks the beginning of codenaming the X Tournament Series events, because of the near-ending 2015 season. Doqtor Kirby considers X10 a "commerical failure", due to the lack of entrants due to a domino effect of events hindering the tournament. The event was run under a Swiss Bracket format with a 4-man top cut.