This product is a brand new and unused Opus Magnum CD Key for Steam.

Immediately after payment, you will be sent a unique and unused CD Key which can be activated on Steam. You can collect this activation code from our Autokey page.  Simply enter your code into the Steam client (available free from steampowered.com). This will then grant you to a full digital download of the game.

How does our website work?

CJS CD Keys sell brand new CD Keys either taken directly from brand new sealed copies of the game, or sourced directly from world-leading game publishers. We source our keys in bulk directly from leading distributors and publishers, which reduces shipping costs.  This enables us to offer instant online delivery, at extremely competitive pricing.

After you receive your key, you can activate the game on the Steam client (available free from steampowered.com). After you activate the game with the Steam software, you can download the game immediately and instantly.

Region Free

This product key we are selling is sourced directly from the publisher, or an official distributor of the game publisher. The key is completely region free and includes all languages. Region free means that you can activate the product code from anywhere in the world.

About Opus Magnum:

“It is not an exaggeration to say that without alchemical engineering, civilization would not exist.”

Hailed as the most promising alchemist of his generation, Anataeus Vaya has just accepted a position as Head Alchemist of House Van Tassen, the oldest and richest of the city’s ancient Houses. But dangers lurk behind the family’s opulent facade, and alchemy alone may not solve every problem.



Opus Magnum is the latest open-ended puzzle game from Zachtronics, the creators of SpaceChem, Infinifactory, TIS-100, and SHENZHEN I/O. Master the intricate, physical machinery of the transmutation engine— the alchemical engineer’s most advanced tool— and use it to create vital remedies, precious gemstones, deadly weapons, and more.

Design Machines - Design and build machines that carry out alchemical processes using a variety of components including programmable arms, customizable tracks, and more esoteric devices like Van Berlo’s wheel and the Glyph of Animismus.

Open-Ended Puzzles - Compete against your friends and the world to build the simplest, fastest, and most compact solutions to the game’s challenges. Export animated GIFs of your elegant designs to show them off.

Steam Workshop - Make and share your own puzzles with full Steam Workshop integration and an easy-to-use puzzle editor. Play the top user-submitted puzzles in the prestigious Journal of Alchemical Engineering, curated by Zachtronics!

Rich Story - Intrigues and dark plots swirl around the city’s ancient Houses. Alchemists, who hold the power to create almost anything known to science, are highly sought— and highly dangerous.

Solitaire Minigame - Alchemical engineering takes focus and concentration. Take a break with Sigmar’s Garden, an original alchemy-based solitaire game. Every game is winnable, but not every game will be won…