Main Assembly

Released Jan 2021

You’re the designer, engineer and architect if you can imagine it you can create it! Construct robots of any shape or size from eight-legged spider bots to eerie UFO contraptions.

82% positive · 1,355 reviews

Done

All announced content has been released

Medium confidence

Done

All announced content has been released

Medium confidence

Where to buy

Steam Updated 12 Oct 2026 $19.99 Green Man Gaming Steam key Updated 12 Oct 2026 $19.99 IndieGala Steam key Updated 12 Oct 2026 $19.99

Prices in USD, as listed by each store.

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Evaluation

Main Assembly left Early Access and launched as version 1.0 on January 26, 2021, shipping the "Final Frontier" space update alongside that release. During Early Access (mid-2020 through January 2021), Bad Yolk Games delivered five major content updates at a brisk pace: Update #1 "Break It" (July 2, 2020), Update #2 "Co-Operative Pack" (August 6, 2020), Update #3 "World Building V1" (September 15, 2020), Update #5 "Bot Brawls / World Building V2 / Water Physics" (November 9, 2020), and finally the 1.0 Space update (January 26, 2021). After launch, the only post-1.0 developer communication was a patch update on August 11, 2021 (version 1.1, made available first on the beta branch) addressing player feedback and fixing bugs. There have been no further developer news posts, no announced DLC, no roadmap for post-launch content, and no unreleased items in the DLC listing. The August 11, 2021 patch is the last confirmed developer activity on record. The rapid pre-launch update cadence was entirely an Early Access phenomenon; after 1.0 shipped, no sustained post-launch content pattern was established. The game appears to have launched as a complete product with one follow-up polish patch, and no further content has been signalled by the developer.

Evidence

Main Assembly 1.0 launched out of Early Access, including the new 'Final Frontier' space update with zero gravity, a space station sandbox, rocket engines, and lasers.

news post · Jan 26, 2021 source content shipped

high

Version 1.1 patch released to the beta branch, addressing player feedback with a range of bug fixes and quality-of-life improvements. This is the last recorded developer communication.

news post · Aug 11, 2021 source development ongoing

medium

Media

Details

Developer

Bad Yolk Games

Publisher

Team17

Achievements

Platform

Windows

Controller

partial support

Steam Deck

Playable

Players

Single-player · Multiplayer · Co-op · PvP

3D Sandbox Building Simulation Programming Robots Physics Science Artificial Intelligence Crafting Management Logic Automation Immersive Sim Education

About this game

You’re the designer, engineer and architect if you can imagine it you can create it! Construct robots of any shape or size from eight-legged spider bots to eerie UFO contraptions. Engineer each and every appendage with powerful visual programming letting you dictate the bots every move. When you’ve completed your masterpiece, open the world builder and craft the ultimate obstacle course to push your bot to its limit.

Alone or with fellow inventors, envision your design then make it a reality.

Create a world in which your bots will be challenged. Craft tracks for racing or complex obstacle courses that tease out all those lovely design flaws you didn’t know you had.

Show off your designer skills first-hand with up to three friends. Build worlds together to challenge each other's bots in different obstacles courses and tracks. Or smash each other's creations into metallic pulp (more coming soon).

No friends? No problems. We’ve created a single-player mode with over 100 challenges to test your inventions.

Don’t panic, we don’t expect you to code in C# (we’re doing that). In fact, it’s entirely optional, but if you’re up to the challenge we’ve designed a powerful visual programming tool for you to enhance your creations.