You can't have video games without music. Well, you can---the earliest games didn't have music in the strictest sense, just beeps and boops. But it wasn't long before the two became inseparably linked, and now a 150-year-old saucy Russian folk tune is known as "that song from Tetris." Today, developers and publishers put huge amounts of time, money, and consideration into the music that foes into their games. But if you'd rather play with your own meticulously-curated local collection, there are plenty of games that are happy to let you do so.

The key is a technique called procedural generation. Developers have created systems that can analyze a music track---any music track, so long as the original file is in a DRM-free format---and have the game automatically create a level around it. The idea has been around for a while, and made its way into a variety of game types and genres. Here are the best picks for PC gamers.

Audiosurf 2 (Windows, macOS, Steam, Linux)

Audiosurf started off the procedural music genre when it debuted back in 2008, and some of the same technology powers other games. But the sequel, Audiosurf 2 ($15), includes a bigger selection of built-in tracks, a collection of player-customized song levels via the Steam Workshop, and integration with the SoundCloud online repository. The original mechanics remain intact---it's sort of like playing Tetris on a Guitar Hero screen---along with new and varied game modes. more player ships, better graphics, and more visual effects. The modding community has embraced Audiosurf 2 with enthusiasm, meaning you'll never run out of new game modes or levels, and each one comes with its original scripts if you'd like to try your hand at modding yourself. There's a free demo that lets you play the Song of the Day, if $15 is too rich for your blood.

Beat Hazard (Windows, macOS, Linux, Xbox 360, PS3, Android, iOS)

Beat Hazard ($10) is a top-down, twin-stick shooter in the vein of Geometry Wars, with space levels and enemy ships generated by the algorithm of your local music. In addition to hitting that musical pleasure center of your brain while you dodge bullets and blow up ships by the dozen, the game features local multiplayer in both co-op and head-to-head modes. The faster the beat of the music, the more intense the enemies and the more powerful your weapons become. But don't worry: even if you try to play the game to golden oldies and slow jams, the difficulty will ramp up in survival mode. Beat Hazard even supports online radio stations, in case your local collection is a little thin. The DLC upgrade, Beat Hazard Ultra ($5), includes online multiplayer, new enemies and weapons, and extra visual goodies.

Symphony (Windows, macOS, Linux)

Symphony ($9) uses a similar setup to Beat Hazard, but with a more traditional top-down "bullet hell" playing field, like Galaga or 1942. The hook is pretty interesting as well: the enemy can "corrupt" your music as it gains the upper hand. Each level procedurally generated from a song track includes a unique item for collection and upgrades, allowing players to push past higher difficulty levels and tougher bosses. Support for most common music file types is included, though you'll have to pay an extra dollar for compatibility with iTunes and its M4A/AAC file formats.

Crypt of the NecroDancer (Windows, macOS, Linux, Xbox One, PS4, PS Vita, iOS)

Here we have a fairly typical roguelike dungeon-crawler that lets players move along the grid-based floor and power-up their attacks based on the music playing in the background. While Crypt of the NecroDancer ($15) allows players to import their own tunes and play along with procedural levels and enemies, it's also been praised for its original score, a thumping, beeping electronica mix from composer Danny Baranowsky. There are also plenty of DLC packs that double as both musical add-ons and extra levels. Unlike most of the simple fare on this list, Crypt includes some complex combat and RPG mechanics. Don't let the 2D sprite graphics fool you---there's more depth in this game than can be seen at first. Also, it supports DDR-style dance pads for active game inputs, and the singing RPG item seller is named Freddy Merchanty. Come on, you know you love it.

Melody's Escape (Windows, macOS, Linux)

On the surface, Melody's Escape ($10) looks like a fairly typical "endless runner" game, as is so often seen on mobile. But the custom engine it uses to create levels and obstacles from musical tracks might be the most complex here---watch the video to see the impressively smooth transitions from fast to slow gameplay and back, based on the shifting beats per minute of the current track. There's also a refreshing variety of moves and enemies, and though the 2D vector graphics are simple, they communicate the immediacy of the level very effectively. This indie game is low on extras, but for $10 (less if you catch it on sale), it's more than worth the price.

Audioshield (PC/HTC Vive/Oculus Rift)

If you've invested in a full VR setup, you're already familiar with working from a limited selection. At the moment, the only rhythm game of note for the Oculus Rift or the HTC Vive is Audioshield ($20), which uses left and right motion controllers for "shielding" the player against procedurally-generated incoming notes (or missiles, or paint splatters---it's all pretty conceptual). Compared to some of the other games here, the actual mechanics are pretty sparse, but combined with player motion for the entire song it should still keep you more engaged than standard mouse and keyboard controls. Support for online tracks on YouTube, plus online leaderboards, is included. Expect more complex entries in this admittedly small niche to become available in the future.