Kodansha Game Lab has opened the Steam store page for its physics simulation game Legacy Code (レガシーコード) and started accepting wishlist registrations.
In Legacy Code, players freely combine a wide range of parts, from biological materials to inorganic objects, to build a mysterious creature called a "Mechanimal" and set it in motion. The game's original "Marionette Engine" physics system keeps any combination of parts moving without breaking down, producing unpredictable Mechanimals whose behavior is impossible to read, even for the person who built them.
The game has been selected as one of eight finalists for Sense of Wonder Night 2026, an indie game contest held as part of Tokyo Game Show 2026 that looks for titles with especially original ideas. Legacy Code's originality stood out among more than 1,500 entries submitted from around the world.
The Steam store page is now open. Wishlisting the game brings updates as they're announced.
Steam store page: https://store.steampowered.com/app/3354380
PV: https://www.youtube.com/watch?v=g1RuLLMhmx4
About Legacy Code
Legacy Code is a physics simulation game in which players combine odds and ends into a mysterious creature called a "Mechanimal." By freely mixing parts such as heads, arms, legs, and motors, each Mechanimal that comes together ends up looking and moving differently.
The game's biggest feature is its original physics simulation, which lets a Mechanimal move properly no matter how outlandish the combination of parts. A body built with one motion in mind often ends up walking in a completely unexpected way. Not even its creator can tell how it will turn out until it's actually set moving, and that element of chance is at the core of the game's appeal.
Build, Battle, Collect: A Gameplay Cycle That Keeps Expanding
The game's core loop has three steps: "build" (assembling parts), "battle" (setting the finished Mechanimal loose to fight and explore), and "collect" (gaining new parts through battle). Players customize their creature with the parts they earn and head back into battle, repeating the loop to raise their own strongest Mechanimal. This cycle changes not just how the Mechanimal looks, but how much of the world players are able to explore.
The More Parts You Combine, the Stronger and Bigger It Gets, and the More of the World Opens Up
Players guide their Mechanimal through deserts, snowy mountains, and even ruins, running into new enemies at every turn.
Winning a battle yields the defeated opponent's parts. As players add and rearrange new parts, their Mechanimal's body visibly grows larger and more powerful: more legs to support it, arms that reach farther, and heavier blows with each hit. The stronger it gets, the more formidable the enemies it can take on, and the more of the world opens up to explore.
What starts as a small collection of odds and ends can eventually grow into a towering form. Each pass through the build, battle, and collect loop makes a Mechanimal bigger, stronger, and more uniquely its own.
Heads, Fangs, Even Electric Fans: Endless Ways to Build
Mechanimal parts are drawn from all kinds of everyday objects: doll heads, character goods, electric fans, televisions, 3D puzzles, dentures, chains, cacti, and more. Each part has its own look and its own quirks of movement, so the combinations players choose dramatically change how a Mechanimal looks and behaves. Familiar yet oddly shaped junk takes on new life in the player's hands.
Selected as a Finalist for Sense of Wonder Night 2026 at Tokyo Game Show 2026
Legacy Code has been selected as one of eight finalists for Sense of Wonder Night 2026, an indie game contest taking place on Thursday, September 17, 2026, at the Makuhari Messe International Conference Hall as part of Tokyo Game Show.
The contest looks for game ideas that spark a "sense of wonder," the feeling that the world shifts slightly the moment you see the concept or hear about it. This year, eight titles were chosen from more than 1,500 submissions, and each finalist's creator will present their game in person on the day. Legacy Code's selection recognized its unique premise: unpredictable creatures born from junk.
Creator Profile
127号室
X: https://x.com/room_127_lc
A game creator who developed the original physics system called the "Marionette Engine" and keeps building strange creatures with an unsettling, distinctive way of moving. Legacy Code is their first release.
Product Information
Title: Legacy Code (レガシーコード)
Platform: Steam
Steam store page: https://store.steampowered.com/app/3354380
PV: https://www.youtube.com/watch?v=g1RuLLMhmx4
Supported languages: Japanese, English, Simplified Chinese
Genre: Physics simulation
Release: Planned for 2027
Price: To be announced
Players: 1
Developer: 127号室
Publisher: Kodansha Co., Ltd.
Rights: 127号室 / Kodansha
