Behold the marvelous science of alchemy, in which a modest molecule of lead, through careful programming of the transmutation engine, can be transformed into shimmering gold. All this and more is possible in Opus Magnum, a most elegant mechanical puzzle game from the maker of SpaceChem.

From the production-line chemistry of SpaceChem to the electronics programming of the delightfully dense electronics programming of Shenzhen I/O, game developer Zach Barth has spent years creating puzzle games that tap the power of sequential programming. Now out in early access, Opus Magnum is one of his most approachable creations yet.


The player is cast as a new graduate of the Imperial University’s College of Alchemical Engineering. Alchemists utilize a tool called the transmutation engine, an infinitely configurable machine for transforming combinations of elements into new substances. After a refresher course tutorial that familiarizes the player with the various rotating arms, element linking tools and techniques used to program the engine, the player is placed with a noble house, and their alchemist career begins in earnest.

One of the earliest programming tasks involves that old alchemy chestnut, transforming lead into gold. In the world of Opus Magnum, it’s a relatively simple process. All the player must do is configure the machine to apply a special upgrade element to a molecule of lead five times and gold is made. My solution, seen atop the post, is a little rough. I had trouble keeping the arm holding them lead molecule in place, so I built a moving track in order to space things out. Here’s another, more elegant solution.

Utilizing a different sort of mechanical arm, one fitted with a piston, the player who created this solution was much more efficient with space and cost. Whatever, we both made gold.


Another early work order involves creating a waterproof sealant for sailing ships. Here the player must bond three elements into a single structure in order to create the final product. Tools and elements are dragged from the left side of the screen onto the board. Then each moving part is issued a set of instructions—grab, rotate, extend, retract, wait. It’s basic visual programming.

Players can go through their solutions step-by-step, tweaking and adjusting as they go. When their solution is complete, Opus Magnum includes the option to save it as a lovely animated GIF.

Again, not efficient or elegant on my part, but it gets the job done. Ideally the player wants to make a machine that accomplishes the task in the smallest area while requiring the lowest number of cycles, which looks more like this:

Opus Magnum is basically a new take on Zachtronics’ SpaceChem, presenting fake science in a much more polished and attractive way. In fact, it’s an evolution of SpaceChem’s predecessor, The Codex of Alchemical Engineering, a free Flash game that birthed an expansion called The Magnum Opus Challenge.

With a large number of alchemy engineering problems to solve and the ability for players to make and share their own complex creations, Opus Magnum is a mechanical programming puzzle with endless potential.