beatmania IIDX
Arcade Releases
1st - substream - 2nd - 3rd - 4th - 5th - 6th - 7th 8th - 9th - 10th - 11 IIDX RED - 12 HAPPY SKY 13 DistorteD - 14 GOLD - 15 DJ TROOPERS 16 EMPRESS - 17 SIRIUS - 18 Resort Anthem 19 Lincle - 20 tricoro - 21 SPADA - 22 PENDUAL 23 copula - 24 SINOBUZ - 25 CANNON BALLERS 26 Rootage - 27 HEROIC VERSE 28 BISTROVER - 29 CastHour - 30 RESIDENT 31 EPOLIS - 32 Pinky Crush
Foreign Arcade Releases
beatmania IIDX (China) - tricoro (China)
Home Releases
Sony PlayStation 2
3rd - 4th - 5th - 6th - 7th - 8th - 9th - 10th beatmania (2006) - 11 IIDX RED - 12 HAPPY SKY 13 DistorteD - 14 GOLD - 15 DJ TROOPERS 16 EMPRESS + PREMIUM BEST
PC Releases
INFINITAS - INFINITAS (2020)
Mobile Releases
i-αppli - IIDX i-αppli - ULTIMATE MOBILE

General Information

Released: 2004
Slogan: Revolutionary Energetic Diversification
Songs with generic videos are no longer given Video Production Information in the "New Song" category on the official website, a tradition that has continued for every IIDX AC site since.

Changes

Interface features a lot of red, as the name implies. The core in the "CORE ARENA" series of songs is a common occurance in the theme.
New song names are no longer colored blue on the songlist, but are now yellow.
First arcade style with Hi-Speed 4.
First style with Random+ (available via a secret code)
First style to rely on the e-AMUSEMENT network for unlocks
First style to use the modified Beginner Mode (every song is a 1 and gauge does not decrease)
First style to customize skin backgrounds through Konami's network via mobile phone (E-amusement only).
First style to tell you any and all BPM changes in a song, not just the first part of a song's BPM.
Level 8+ added as the top difficulty.
The network connection implemented in 9th Style was utilized to show a graph on the unused side of the play field. The graph shows your current Ex score, your previous best Ex score, and a "target score" (either the machine best or a score pulled over the network). A global clear rate is also showed for each song on the song select screen.
Users with E-amusement cards will now see a CS-style grade change screen if they boost their scores.
Full combo has a orange rising splash.
New Extra Stage mechanic: Must AA 3 Anothers on Hard to get ES song, last must be a Level 7 Another or higher.
Extra Stage: GENOCIDE
One More Extra Stage: ピアノ協奏曲第1番"蠍火"
Total number of songs: 336

This is the only IIDX game where NAOKI is a sound director. Incidentally, it was he who found DJ Yoshitaka, who made his IIDX AC debut in this game.