Rivalry themes
Rivalry themes are songs that are played when certain characters are chosen by each of the two players while they are in battle. For example, when P1 chooses Sol and P2 chooses Ky in Guilty Gear -The Missing Link-, the song Conclusion will play instead of their character themes. Guilty Gear -Strive- launched without rivalry themes, but gained one in the game's version 1.40 update.
Guilty Gear
In Guilty Gear, the song Conclusion is Sol Badguy and Ky Kiske's rivalry theme and only rivalry theme in the game.
Guilty Gear X
In Guilty Gear X, the song No Mercy is Sol and Ky's rivalry theme.
Still In The Dark is Millia Rage and Zato-ONE's rivalry theme.
Guilty Gear XX
In Guilty Gear XX, the song Noontide is Sol and Ky Kiske's rivalry theme.
Existence is the rivalry theme between any of the Assassin's Guild members (Eddie, Millia, Venom and Slayer).
The Heavy Rock Track version of No Mercy from Guilty Gear X is EX Sol and EX Ky's rivalry theme.
Similar to No Mercy, the Heavy Rock Track version of Still In The Dark is EX Millia and EX Zato's rivalry theme.
In Guilty Gear XX Λ Core, the track "Keep the Flag Flying" was added as the rivalry theme of Order-Sol and Ky. This song has only ever been released on Guilty Gear XX Λ Core Secret Gig, which means that it not currently available for streaming.
Guilty Gear XX ♯Reload Korean Version
The Korean version of Guilty Gear XX ♯Reload contains a entirely new soundtrack composed by the band N.EX.T.
The song Revelations is Sol and Ky's rivalry theme, replacing Noontide.
Rogue Hunters is Assassin's Guild rivalry theme, replacing Existence.
Faith Shall Save Thee is Sol and Ky Type-EX theme, replacing No Mercy (Heavy Rock Track Version).
Red Crossroads is Millia and Zato Type-EX theme, replacing Still In The Dark (Heavy Rock Track Version).
Guilty Gear 2 -Overture-
In Guilty Gear 2, the song The Re-coming is Sol and Ky's rivalry theme.
Communication is Ky and Sin Kiske's rivalry theme.
Guilty Gear Xrd
In Guilty Gear Xrd the song Reunion is Sol and Ky's rivalry theme.
The Spider's Thread (Do you know?) is Millia and Zato's rivalry theme.
When Life Comes is the Assassins Guild rivalry theme.
Communication from Guilty Gear 2 -Overture- is reused as the Ky and Sin rivalry theme.
Guilty Gear -Strive-
As of the version 1.40 of Guilty Gear -Strive-, Get Over Nightmares is the only rivalry theme, being the theme of Ky and Sin.[1]