>you sing to her
>when she gets down half her hp the ost changes and now she's singing to you
Games with an "interactive" soundtrack
>you sing to her
That's some ugly ass tumblr looking motherfucker, kill yourself OP.
yeah it's called guitar hero
Metal Gear Rising: Revengeance.
The first boss fight starts with you on a rooftop slashing away at a Metal Gear (RAY) – once you do enough damage, the fucker jumps away from you and decides to annihilate the rooftop you're on with an absolute barrage of missiles.
Raiden says fuck that and jumps on the fucking missiles, hopping from missile to missile to close the distance between himself and RAY while the vocals kick in and urge you on to kill that son of a bitch.
Each boss fight has its own song that has vocals or instrumentals that kick in after a certain amount of damage has been done or the fight moves to a different area. It feels like you've got an invisible concert following you around cheering you on as you kill things violently.
You're talking about a dynamic soundtrack and many games have them.
One of the most well-knon early examples would be banjo-kazooie, where almost every level shifted between different mixes for some key areas or being underwater.
For this example the hub world has a lot of different versions it shifts between whenever you approach the entrance of one of the main levels.
Phantasy Star IV added more instruments to the overworld music the more characters you had in your party.
Wind Waker played musical notes when you struck with your sword that meshed with the melody of the fight.
In Metal Gear Rising the lyrical version of the song is played during the boss's second half of the fight. When you disarm Sam the lyrics are muted again. There is also dynamic music to ease the transition in music, Bloodborne and Zelda are the first examples off the top of my head that use this but lots of games also use it too. Haven't played the games yet but isn't Phantasy Star well regarded for its dynamic use of its soundtrack and how much it manipulates it?
This is only tangentially related but I really love it when games reward you/encourage you with music. There's the standard way of doing this by having an unlockable music menu/jukebox/etc as you progress through the game. My most memorable use of music as a reward was the quest in Nier where you're trying to get Popola to sing with Devola and the required items are grindy to acquire, but once you did so you were awarded with an amazing version of Song of the Ancients sung by both sisters that made the entire scene incredibly relaxing, soothing, and comfy. That song instantly made the grinding for the materials worth it. You could remain in that bar for as long as you wanted and the song would keep playing. I easily stayed there for 20-30 minutes the first just sitting back and listening to the music. The quest also made what happens later in the game all the more painful.
that's really relevant actually since they obviously have the multitrack versions of songs allowing the game to cut out one instrument when wrong notes are played, but not every rhythm/music game has that
Muramasa gives each normal areas theme a peace variant and a combat variant (considered "A version" and "B version" to the track), with the jump from one to the other being seamless.
Pretty sure I remember Skies of Arcadia also having dynamic boss music, that changed depending on how a fight was progressing.
Also the "A Version" to the "B version" up there.
The Killer instinct reboot has music that gets more intense after big combos or after a combo gets broken, and music gets calmed down when not much is happening
Ikaruga's game design is synced perfectly to the soundtrack.
Skies of Arcadia's battle theme changes in tone based on how well/poorly you're doing.
Lots of games do it. To list a few, Magic Carpet 1 and 2, Deus Ex, Total Annihilation, Freespace 1 and 2, Jedi Outcast/Academy, Dungeon Keeper 2. Some Tetris games when you're under duress. Touhou 13 seamlessly moves to an alternate track when in trance state.
That aspect of the game was godly. Also used in Conker's Bad Fur Day.
Relatedly, Drakengard 3 alters music during Intoner mode. For the stages it's just operatic singing type thing, but the boss fights add chaotic-sounding electronic vocals. Annoyingly the latter aren't in the soundtrack.
A pretty simple one, but Super Mario World adds drums when you ride Yoshi. Also, 5th Gen Pokemon has NPCs that you could ask to play music that then adds a new intrument to the track.
Mystery Dungeon games
There is a single theme which gets changes based on situations and areas.
Space Invaders Exteme also has "dynamic" music which syncs up to your shots.
Phantasy Star Online had a similar system where the music would blend between the regular and 'battle' version of the level theme when enemies appeared. For both of those games, the Gamecube version broke the smooth transitions and just abruptly cuts to the other version of the music. A lot of the sound effects in the Gamecube SoA were badly compressed, too.
I'm not sure what was so special about the way the Dreamcast handled sound but for some reason none of the ports from it ever seem to work properly in this regard. Even the PC version of Jet Set Radio is missing the smooth fades between tracks that the Dreamcast version had.
FYI you're probably looking for "dynamic", not "interactive" music. Anyway, Freelancer's music would change depending on a few things, including whether you're in combat or even certain known hostile regions. The music would wind down and blend back into the ambient stuff after a fight wrapped up. Every region of space had its own set of music, and if I remember right, the triggers were enemies detected and active combat. It's a lot like Payday 2's dynamic music, as you've already mentioned.
To add some extra examples: Battle Chess (fairly light theme early game, darker themes as pieces get captured), F-Zero GX (seamlessly moves into a faster variant of the song during the last lap), most 3D Zelda games (annoying battle theme).
Also in NSMB Wii.
I've only ever played the Vita version of JSR, but that connects tracks like a non-stop mix CD would. Which is cool, but not exactly related to the thread.
The BIT.TRIP games play a note with each successful input. Better play makes the melody and harmony more intricate, while bad play simplifies it until it's reduced to single-tone bloops.