Minhkhoa Khan

During their youths, Khoa trained with many of Bruce Wayne's mentors with the goal of preparing himself for a life of crime-fighting; over the years, the two struck up a friendship due to their shared interests. However, their friendship became strained after Bruce told him that the reason he wanted to become a crimefighter was to avenge his parents; angry that he was doing it for emotional reasons and not for the art of it, Khoa attacked him.

Over the years, Khoa would fight Bruce many times as their paths crossed during their journeys; Bruce would later claim that once he turned 20 years old, he won these fights every time. One of these fights occurred after Khoa followed followed Bruce to Dublin and clashed over the right to learn from Tommy Tivane, the world's greatest knife-thrower. Khoa also seemed to have harmed a mutual master in Morocco, souring their friendship further. He later trained with the Desert Kings in the Gobi Desert for two months; when Bruce went there the next year, he followed him and tried to initiate another fight. Bruce rejected him, as it was the anniversary of his parents death and he wished to be alone, but eventually relented after Khoa claimed that this sentimentality made him weak.

Despite his nature and their disagreements, Khoa was concerned for Bruce and stopped him in Argentina before he left back for Gotham City in a last attempt to appeal to him. Khoa implored him to realize that there is no way he can save everyone, and that operating with this singular focus would eventually wear his soul down to nothing. He asked Bruce to instead join him in southeast Asia where they would systematically destroy criminal underworlds, offering to do the same to Gotham once they had the resources. Disgusted with Khoa's outlook, Bruce warned him not to come to Gotham and Khoa agreed, as he had no interest in the city; in return, it was agreed that Bruce would not step foot where Khoa was operating.

Taking the name "Ghost-Maker", Khoa followed through with his plan; mostly operating within Southeast Asia, he would spend a year taking down criminal operations in whichever city he went, leaving a massive body count and no trail for authorities to discover him. While operating in Singapore, he would eventually cross paths with Bruce (now operating as "Batman") when he tracked down a Gotham criminal who had fled there. Batman begrudgingly agreed to allow the latter to handle the criminal, per their agreement; on the way back, Bruce would confide to his protégé that although he was still furious with Ghost-Maker's selfishness, he also missed being friends. He later tracked down Ghost-Maker and offered him a position within Batman Incorporated, but this enraged him and resulted in another fight.

After the Joker War, Ghost-Maker broke the pact in order to step into Gotham as its new protector, disappointed in how Bruce handled its criminals. He activated his Ghostnet to absorb and analyze all the network infrastructure of Gotham's criminal underworld, and begun processing an action plan to dismantle it. He soon found that a new vigilante was his main obstacle in applying this plan -- a teenager named Bao Pham, going by the alias of "Clownhunter". Given the fact the boy was also a ruthless killer endangering civilians, Ghost-Maker chose him to be a symbolic victim for Bruce to realize his mistakes.

Upon his arrival, Ghost-Maker killed all of the Grinners, a gang of Joker supporters, at their headquarters called the "Smile Bar". He then located Clownhunter while the latter was trying to blow up Harley Quinn's apartment; Batman came to the boy's rescue and the two engaged in combat. Bruce explained that Bao is a teenager who witnessed his parents being killed by the Joker five years before (a murder that Harley was present for), and that he would rather rehabilitate him than kill or imprison him.

Disappointed that Bruce had not changed, Ghost-Maker tranquilized Bruce, Harley, and Clownhunter and trapped them in a room of Arkham Asylum, leaving only Clownhunter unrestrained in order to force Bruce to handle him. However, the plan did not work as Harley managed to break through to the teenager by explaining her resolve to atone. Batman related that although it was true that not everyone can be saved, caring for people like Harley and Bao allowed them to get better and make a difference. Although Batman has come close to death many times and his work would probably never be done, he believed the success he has had with rehabilitating people over the years prove that empathy has its place.

Satisfied with Bruce's answer for the time being, Ghost-Maker initially intended to leave, but Bruce believed he would need help in a rapidly-changing Gotham and asked Ghost-Maker to stay with him -- as long as he does not kill. Seeing it as an interesting challenge, Ghost-Maker accepted and two began tackling the mysterious reemergence of Scarecrow and a radical transhumanist movement in Gotham called the Unsanity Collective, all while evading targeted aggression from the city's new Peacekeeper program. To this end, Ghost-Maker had a high-tech base built within Gotham, which he designed to top the original Bat-cave; he christened it "The Haunt".