Game Randomizers: Procedural Variations on Your Nostalgia

By Jo Mazeika (Twitter)

One of the Hot New Trends (trademark) on Twitch are game randomizers. Randomizers take a game, and shuffle around different parts of it, from the locations of items, to enemy stats and abilities, all the way up to generating entire new dungeons or overworlds. By doing so, they grant players the opportunity to explore a once-familiar space with new eyes. While they don’t tend to alter the mechanics of a game (excepting some player conveniences or bug fixes), they instead offer a player the chance to explore a game in a new and unique way, recapturing some of the experience of being able to explore a world again for the first time. Many of these randomizers come out of speedrunning communities, and as such, most allow the players to specify the random seed used so that if players are racing to beat the newly randomized game, they’re both on equal footing.

What makes the generation aspect interesting are the constraints that the pre-existing game imply for the randomizer. It’s not enough randomly shuffle things; the game still needs to be beatable, and in most games, there are a number of configurations that will wind up unbeatable. To overcome this, constraints need to be placed on the system, leading to a complicated series of logic constraining different items and locations on the positions of others. Depending on the game, this can be a huge nightmare — the most popular randomizer, the Link to the Past randomizer ( ), has around 30 different items that can be used to open up new locations within the game and all of these need to be accounted for when generating a new seed for players to explore. Other game randomizers, such as the Dragon Warrior randomizer ( and the randomizer for the original Zelda ( also generate their worlds as well as shuffling the items — the Zelda 1 randomizer shuffles the caves on the overworld, and has the ability to generate dungeons from scratch, while the Dragon Warrior randomizer completely generates a new overworld, while leaving all of the dungeons and caves alone. In all of these cases, it’s important that all of the important locations are reachable, and...

These systems represent an alternate approach to game generation — instead of trying to build a game generator from scratch, randomizers start from an existing game and explode its possibilities outwards, to the point where the generated experiences can be completely unlike the original’s play. The Link to the Past randomizer has modes where finding certain items requires the use of glitches of varying degrees, allowing highly skilled players to test their skills. The Final Fantasy 4 Free Enterprise randomizer ( turns the linear, narrative-driven game into an open-world treasure hunt by giving players access to two of the playable characters and an airship, and letting them explore the world from there. The Final Fantasy 1 randomizer ( not only gives players fine-tuned control over the gold and experience scaling within the game, but features overworld changes, designed by the community to make certain items more valuable as well as the ability to shuffle around all of the towns, dungeon floors and caves to make completely new spaces to explore. While most of these systems stay close to their original play experiences, each new feature allows for an even broader range of possibilities for these systems.

In short, game randomizers are a fascinating example of PCG out in the wild, generating new scenarios and new spaces for existing games. They offer a way of exploring the possibility space of a given game’s world and mechanics, and they’re a great way to re-experience a beloved classic in a new light.