The King of Fighters '99: Millennium Battle, also called KOF '99, is a 1999 fighting game developed and published by SNK for the Neo Geo arcade and home platforms. It is the sixth installment in The King of Fighters series following The King of Fighters '98, introducing a new story arc known as the "NESTS Chronicles" which is centered around a young man named K', who is formerly associated with a mysterious organization known only as NESTS. The game introduces several changes to the established KOF format, most notably an assisting character labeled "Striker". The game was ported to the Neo Geo CD and the PlayStation. Dreamcast and Microsoft Windows versions were also released under the title whose stages were remodeled in 3D.

SNK had originally planned to remove main characters Kyo Kusanagi and Iori Yagami, who had previously appeared in earlier installments of the series, from The King of Fighters '99, but they ended up as hidden characters instead. The popularity of Kyo's previous incarnations resulted in him being given "clones" that wear his original clothes and perform his moves. SNK had difficulty balancing the age of the characters and teams. The Neo Geo AES and Dreamcast versions are both included in The Kings of Fighters NESTS Hen compilation released for the PlayStation 2 in Japan alongside other ports.

Critical response to The King of Fighters '99 has generally been positive because of its fighting system and its use of Strikers. The Dreamcast port of the game has had a more favorable reception than the PlayStation version thanks to its loading times and graphics. While the game has sold well with a total of 168,000 copies, overall sales have been less than those of the series' previous game because of poor sales of the console versions. The game was succeeded by The King of Fighters 2000.

Gameplay

Instead of the three-character teams from earlier The King of Fighters (KOF) games, each team now has four members. Before a match, the player chooses three of the characters to use in the fights. The fourth member becomes the "Striker" the player summons during battle to help their character by performing one of their Special Moves against the opponent. A Striker can be summoned only a limited number of times during a single match. This is determined by the number of "Strike Bombs" at the bottom of the screen.

The selectable fighting styles, Advanced and Extra, from The King of Fighters '98 have been removed. Instead, the game has a single playing style modeled after the Advanced mode from the previous game, where the player fills their power gauge by attacking the opponent or performing special moves. This time, there are two powered-up states the player can choose during battle depending on the button combination used. Counter Mode increases the player's offensive strength and allows them unlimited use of their character's Super Special Move. There is also a combo that transitions from a Special Move into a Super Special Move by using a "Super Cancellation Attack" or a "Moving Attack". The other powered-up mode is Armor Mode, which increases the character's defensive strength, allowing them to take more damage from the opponent; however, the player cannot use Super Special Moves in Armor Mode.

Depending on the player's performance, a score is given when the fight is finished. Should a high score be reached, the arcade mode will offer the player an extra fight following the final boss; Kyo Kusanagi or Iori Yagami.

The updated The King of Fighters '99: Evolution version features stages remodeled in 3D and includes two additional stages, as well as new characters who can only be used as Strikers. The new Strikers are Kyo Kusanagi (in a different outfit), Athena Asamiya (in her school outfit), Goro Daimon, Billy Kane, Ryuji Yamazaki, Chizuru Kagura, Syo Kirishima, Alfred, Vanessa, Seth, Fiolina Germi, and Gai Tendo. Also, the game can be connected to the Neo Geo Pocket Color game The King of Fighters: Battle de Paradise. Points won in Battle de Paradise can be transferred to The King of Fighters '99: Evolution to speed up the leveling process for the Extra Strikers.

Plot and characters

Two years have passed since the last King of Fighters tournament. Nobody has seen Kyo Kusanagi or Iori Yagami since they defeated the evil being Orochi at the climax of the 1997 tournament. Invitations are sent to many characters inviting them to a new tournament, which this time around is more of a secretive affair and away from the public eye than the ones in both '96 and '97, with each team now having an additional member. However, the tournament's host remains unknown.

The increased number of characters per team, and the story element of the missing Kyo and Iori, lead to a reshuffling of the character roster. K' is introduced as the game's new protagonist with his partner, Maxima, who joins forces with Kyo's former teammates Benimaru Nikaido and Shingo Yabuki to form the new Hero Team. Takuma Sakazaki rejoins the Art of Fighting Team as its fourth member. Mai Shiranui finally becomes an official member of the Fatal Fury Team for the first time in the series. The new Female Fighters Teams is composed of Art of Fighting guests King and Kasumi Todoh, Fatal Fury characters Blue Mary and Li Xiangfei with the latter making her debut in the KOF franchise. The three returning teams also gain a new member: Whip for the Ikari Warriors Team, Bao for the Psycho Soldier Team, and Jhun Hoon for the Korea Justice Team. The game also introduces two clones of Kyo Kusanagi, Kyo-1 and Kyo-2, as Team Edit characters based on previous playable incarnations of the character. The real Kyo also returns with his rival, Iori, but they are only secret playable characters.

The game's antagonist is Krizalid, an agent from the mysterious organization NESTS who uses the data he obtained from his enemies to activate an army of Kyo clones that NESTS themselves had created after the fight against Orochi. He is faced in two states: first he appears with a special coat that analyzes an opponent's data. Once he's defeated, he burns away his coat and increases his strength while having stronger moves. After Krizalid's defeat, his superior kills him via falling debris while other members of NESTS attack K' and Maxima, who are revealed to be former NESTS agents and that the duo succeed in defeating their enemies before making their escape from the collapsing location of their battle against Krizalid. It's also revealed that K' is a test subject designed to replicate Kyo's techniques.

New characters are marked below in bold:

K' Team (Hero Team) K' Maxima Benimaru Nikaido Shingo Yabuki Fatal Fury Team Terry Bogard Andy Bogard Joe Higashi Mai Shiranui

Art of Fighting Team Ryo Sakazaki Robert Garcia Yuri Sakazaki Takuma Sakazaki Ikari Warriors Team Leona Heidern Ralf Jones Clark Still Whip

Psycho Soldier Team Athena Asamiya Sie Kensou Chin Gentsai Bao Women Fighters Team King Blue Mary Kasumi Todoh Li Xiangfei

Korea Justice Team Kim Kaphwan Chang Koehan Choi Bounge Jhun Hoon Single Entry Kyo Kusanagi Kyo-1 Kyo-2 Iori Yagami Krizalid

Development

The King of Fighters '99 was the last KOF game with producer Takashi Nishiyama due to issues with the company in 2000. Like the earlier games the artwork was done by Shinkiro. Hiroyuki Kono from SNK said that with The King of Fighters '99 the team was trying to provide new content that previous games lacked. The new characters were decided within the recurring teams to properly fit. Kono thought that of the Striker idea as a change to the franchise in general. With the Strikes system where the fourth character assisted the playable character, SNK aimed to give the player new ideas for combos. However, it still brought several challengers. The story was written with the idea of a new storyline different from the Orochi arc used in previous installment and be more accessible to newcomers. As now every team has one additional character, the developer wanted to expand on the lore, establishing new relationships. The story of the new protagonist K' in The King of Fighters '99 set to be the beginning, Kono already planned the narrative to be further explored in at least two installment and exceed the fans' expectations.

The designs in general were retouched to give a cooler emphasis, most notably in K' as his sophisticated style is meant to breathe new life into the series. Eiji, one of the game's designers, commented that he thought K' would be more popular than he turned out to be, noting that K' was too plain. As the game was developed at the same time as SNK's Garou: Mark of the Wolves, the protagonist's designer was fearing he was too similar to Rock Howard which made him nervous. There were also similarities with Cool from the fighting game The Fallen Angels as its designers moved to SNK to work in The King of Fighters '99. Kyo and Iori were originally designed by Shinichi Morioka who had left Steel Hearts after The Fallen Angels and upon returning to SNK for The King of Fighters '99, he also created K' and Maxima.

With the introduction of a new lead character, K', SNK had originally planned to remove main characters Kyo Kusanagi and Iori Yagami, who had previously appeared in earlier installments of the series, from The King of Fighters '99. Instead, they ended up as unlockable hidden characters after fans responded negatively to their removal at location tests. Kyo and Iori were supposed to disappear due to business reasons or the requests of enthusiastic fans, but in the end they have continued to appear ever since. Kyo was involved in the story to some extent, but not Iori, in terms of the connections with the new protagonist. The same issue would happen in the third story arc, where Kyo and Iori are major characters opposing The King of Fighters 2003 lead Ash Crimson but more due to narrative intended reasons rather than fan demand.

Kyo was redesigned for this game for the first time in the entire series replacing his school uniform with more casual clothing that were well received by the staff and fans. However, developers still liked his school uniform. As a result, based on the practice of adding earlier versions of various characters to games, the staff created the Kyo clones that featured him with classic movesets: Kyo-1 uses Kyo's movesets from the first two games, while Kyo-2 uses his movesets from KOF '96 and KOF '97. To contrast with the previous series' protagonist, Kyo, K' was designed to be the "dark hero". The staff wanted to create a Robo Army Team. This idea was abandoned, but they later created a tribute to it in The King of Fighters 2000 by introducing Rocky, a character from Robo Army, as a Striker for Maxima. The character Whip was originally meant to appear in KOF '96, but due to Leona Heidern's introduction in that game, the staff decided to wait until KOF '99.