Secret Trick × Registration × The Battle Begins (裏ワザ×登録×バトル開始, Uchiwaza × Tōroku × Batoru kaishi) is the 39th episode of the original Hunter × Hunter anime. It first aired on September 16th, 2000.
Gon and Killua make it past Hisoka's Ren and sign up for fights on the 200th floor of Heaven's Arena. Gon wants to test his new powers and fight a man who uses his Nen on toy tops as weapons. During the fight, Gon learns Zetsu to sense the tops and avoid them, but is eventually beaten.
