Protoss builds. Having participated in high-level competitive matchups since 2006, Bisu made his breakthrough at the 2007 MBCgame Starleague (MSL) final, defeating experienced players Nal_rA and sAviOr, both 3:0. At that time Bisu was one of the few Starleague Protoss players. He qualified for the 2007 MSL automatically for having received a KeSPA distinction as the best Protoss player. Prior to the breakthrough match with sAviOr, which is sometimes referred to as "March 3rd revolution", Protoss players generally underperformed against Zerg. However, this was soon to change. During Bisu's preparations for the match with sAviOr, the MBCGame HERO coaching staff, as well as Protoss and Zerg players gave Bisu some ideas. The general advice was to use Corsair units to eliminate Zerg Overlords, narrowing Zerg's observation. Bisu's effective execution of this strategy found great success. Following Bisu's victory, several players started to emulate his winning Corsair–Dark Templar combination to fight Zerg opponents. In the first half of February, 2008 Bisu (who was already atop of the KeSPA ranking, the first protoss to achieve that) was transferred from the MBCGame HERO team to SK Telecom T1. The latter team failed to score good results in leagues and confront the new generation of professional gamers, and the entire coaching staff was dismissed. Players iloveoov and Kingdom were promoted to coaches instead. To fill the gaps and to improve the performance results, SK Telecom T1 acquired Bisu. Bisu later called his transfer "definitely a turning point" for him as a gamer. In 2009, to fill up the schedule, OnGameNet arranged an All-Star Race Battle, where four players of each race (Protoss, Terran and Zerg) would compete in a knockout series. Bisu defeated the Terran lineup of players Flash, Hwasin, Leta and NaDa, but failed to score a win against sAviOr. In the fall of 2008 Zerg players adopted a three-base five-Hatchery strategy against Protoss and nearly all attempts to counter it failed. Protoss players had particular difficulty using Zealots against Hydralisks in a choke battle as the Zealots could not spread out effectively, while Hydralisks could clump easily, not allowing Zealots to take advantage of their speed upgrade. Bisu managed to successfully use speed-upgraded Zealots to obtain map control and engage the Hydralisks before they reach mass numbers. While other professional Protoss players have around a 60% win ratio against Zerg, Bisu's ratio against that race reached over 90% in the 2010–2011 competition