Zero is one of the higher-ranked agents of "NESTS". The designer, C.A.C Yamasaki, admits basing Zero off a certain character from the manga Fist of the North Star. He begins to secretly build his own weapon from NESTS' technology called the "Zero Cannon", setting it to operate. He sets his plans into motion in The King of Fighters 2000. There, he impersonates a military commander named Ling and uses his persona as s decoy to stop the military resistance against him. Depending on the actions of the player, his plans are foiled by either Heidern or Kula, who is sent to execute him for his treacherous acts.
However, the Zero in The King of Fighters 2000 is revealed to be a clone from the Original.
The Fist of the North Star character Zero is based on is clearly Han from the second anime series. Zero and Han have the same hairstyle and moustache, and Zero's "dark Explosion" (jokingly called the "Fart") move is derived from the anime. The scene in which it occured is slightly difficult to describe properly: Han faces an assassin, and kneels in front of him, inviting him to attack. What appeared to be a light gust of wind passes past them both, and then Han stands, turning around and saying that "I attacked so fast that none of you could see it." Another gust of wind passes, and his enemy falls into pieces. The choreography in this sequence was almost identical to Zero's move, minus the purple shadow in the video game attack.
During The King of Fighters '99, Zero was commanded to watch over the performance of the Kusanagi cloning process, set fourth by one of their lower ranked officers, Krizalid. Acting as the project supervisor, he monitored all actions done by Krizalid and also analyzed the performance of K'. After he neutralizes the Kyo clones and terminates Krizalid, he begins to secretly build his own weapon from NESTS's technology called the "Zero Cannon", setting it to operate with the same technology found in Krizalid's battle armor.
He sets his plans into motion in The King of Fighters 2000. There, he impersonates Ling, a military commander and close friend to Heidern. Using his Ling persona as a decoy, he tricks and captures Heidern to stop the military resistance against him. He then fights the winning team of the tournament, planning to use their fighting capacities to power his Zero Cannon. His plans were foiled by Kula Diamond, Foxy, Diana and Candy Diamond. The game's story highly implies that he is killed by Whip after he privately reveals some shocking information to her (this is made more clear in the Japanese version where she aims her gun at him and the shot is audible).
In spite of being Zero's clone, this Zero is very ambitious and betrayed NESTS to fulfill his ideals. He dislikes traitors, but is a traitor himself. As a master impersonator, Zero is able to mask his own personality and copy the personality of others.
- The Dark Arts - Zero has several powers related to darkness.
- Shadow Trap - Zero can stretch his own shadow and make it hold the enemy's feet.
- Dark Explosion - Zero can create a small explosion of dark energy.
- Black Hole - Zero can create a black hole by punching the ground or simply opening his hands.
Zero relies on his special suit to fight. He knows some basic fighting moves, but uses his suit's blades to fight.
- Slasher Zero - The King of Fighters 2000
- Dark Gravitation - The King of Fighters 2002 Unlimited Match