Ayane's 6th costume is based on Millennia, the protagonist from the Tecmo game Kagero: Deception II.
Helena's 3rd costume is a reference to Reina, the protagonist from the Tecmo game Deception III: Dark Delusion.
Tina's hair color was changed from brunette in Dead or Alive to blonde in Dead or Alive 2.
The code of an early version of Dead or Alive 2 lists Genra and Raidou as being part of the roster, suggesting that they were going to be in the game early on in its development.
Zack's 5th costume and Tina's 4th costume are references to characters from the 1999 run of the Shadow Man comics.
In Ayane's Story Mode, if the player beats Kasumi with an attack that launches her across the area, the ending cutscene will show Ayane finishing her opponent off with a ninpo attack.
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Software publishing company Westside, known for making video game code extraction software and gaming hacks, released a hack that allowed users to strip the clothing off of the female character Kasumi. Tecmo brought the company to court on copyright infringement charges and won, forcing Westside to pay 2 million yen in damages.
The first release of the PlayStation 2 version is actually an unfinished port. The development team was given two months to port the game, but before the deadline was up, the company's sales general manager asked to borrow a copy of the game and took it to production on that day. This sent the creator, Tomonobu Itagaki, into a deep depression and almost made him quit making video games. Soon after, Itagaki and his team went back to overhaul the game to create the much improved Dead or Alive 2: Hardcore.