
Photochemistry is a challenging 2D puzzle game about synthesizing chemicals to sustain plant life in a post-apocalyptic setting. Design and construct elaborate mechanisms to produce complex compounds from simple particles.
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Languages: English, Simplified Chinese
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First thoughts and act 1 playthrough: https://www.youtube.com/watch?v=joQ9GR5giNg Photochemistry is a pretty good, interesting, complex, and fairly difficult puzzle game that puts large emphasis on unique and individual ways to solve puzzles, dependent upon the way your mind can construct a solution. There isn't any one ascribed "correct" solution for anything, which is both a blessing and a curse: the game trusts you with the tools and sets you loose, putting the onus of creativity upon the player, which drives a greater sense of triumph over the given puzzles compared to others in the genre. The puzzles consist of constructing compounds out of individual molecules; you are a robot in the post-apocalypse who needs to ensure that plant life can survive ad infinitum, and you must construct pathways for molecules to travel along and bump into eachother to create a final compound. The general vibe is pretty great - you spend most of your time in the puzzle screens, but the "overworld" outside of those, where you control the robot, is like a PS1-era hyper-stylized abandoned laboratory. Love the place-setting and concept overall. There is a plot (that I haven't fully unraveled yet) regarding your finite power supply as a robot and the urgency of your mission to sustain plant life. You're like if WALL-E was a botanist/scientist rather than a garbageman. Gameplay-wise, I found the puzzles to be legitimately quite challenging - though I may be a bit smooth-brained, so take it with a grain of salt. It took me 45 min to get through the tutorial alone, and a further ~2 hours to conquer Act 1. With three different acts, this portends quite a bit of gameplay, especially since I'm sure the puzzles only get more challenging from there. Though I found myself frustrated at times, that's the case with all good puzzle games - and it makes it all the more satisfying when you muscle through that challenge and find a completely unique "I can't believe this works" solution. There's even the ability to make .gifs out of the solution you made up, in case you want to share it with other competitors - and, speaking of competitors, there's even leaderboard functionality for each individual level, allowing you to compete in optimizing your solutions (AND painting how different all solutions are!). It's also worth mentioning that, though there are 8ish levels in each Act, it seemed like you only needed to complete 6/8 to progress to the next one - which is a great consolation from the dev to allow folks who may get stuck on one or two the ability to move forward and not get completely stuck on any one solution. Overall, I think this is a really cool idea with excellent execution from a solo dev, and it's definitely worth the price if you're looking for an interesting and different take that will force you to flex some brain muscles.
Played only a bit so far but a really solid automation game. Really love the asterisks in the graph to tell you "Hey! you haven't unlocked a part they have used yet! That good of a solution might be impossible!" Really cute soundtrack. Really enjoy the niche interactions. Also like that the graph incentiving the mixed play of optimizing cost and speed at the same time that is usually ignored. Definitely worth playing if you like games like Zacctronics!
literally the best anime fantasy mmorpg 2d fighter tower defense visual novel game i've ever played HIGHLY RECOMMEND
This is a very challenging but super fun puzzle game. I haven't been so engrossed in just casually solving problems like these in so long. At one point I was playing for what felt like a half hour and ended up being 3.5 hours. I think what makes this game so compelling is that there are sooo many solutions you could find, and it really is just a game of which one can you find and how does it stack up to what everyone else had. Can you find the most optimal solutions? I only found it thanks to Olexa's video playing it. I finished the game other than some of the extra levels. It’s definitely a hidden gem for puzzle games so you should give it a whirl. Hopefully the game can get more traction because I’d love to see the spread of solutions people are able to come up with.
Really nice Zach-like game. Simple and complex at the same time, and you can get quite creative with your solutions. Looking forward to playing more of it.
Photochemistry is a wonderful little game in the Zachlike sub-genre of puzzle games that I've really enjoyed so far. In it you're asked to form various chemicals to help our robot friend maintain the plant life on the planet until the end of his mission. If you're not familiar with the genre it is a puzzle game that has a focus on creativity and unique solutions. Every level gives you a chemical output as an end goal, maybe a few minor restrictions to usable space, and a wide array of tools to assemble and deliver the finished product. There is no one correct solution and, in the tradition of Zachlikes, there are also different ways of tracking scores (cycles and cost) that usually result in mutually exclusive records for solutions. This allows you to revisit puzzles and take different approaches for making the fastest or cheapest build and adds hours of replayability for those who like to tinker. Photochemistry manages to deliver a fresh and thoughtful puzzle experience with a good mixture of challenging levels and interesting new mechanics as you progress. The music includes some excellent choices from Eric Matyas' collection, and I thought the graphics were very pleasant to look at. Through a mixture of low resolution rendering and 3D models the visuals for the world have a retro feel with a very distinct smoothness to the animation that reminds me a lot of the rotoscoped pixel art in Another World. Some levels are certainly challenging, but nothing that can't be eventually overcome with a break here or there to mull things over. There is also a nifty feature (which should be familiar from other games in the genre) to record animated gifs of your solutions directly while in game; which makes it incredibly easy to share your personal solutions/road-blocks with friends and the community. The game also works excellently on native Linux (I'm using Ubuntu 22.04) without any compatibility tools. Photochemistry is more than worth the $5.99 asking price when it's not on sale. I'm not even finished with some of the harder puzzles yet after spending a good eight hours on things. It's a great addition to the genre that won't disappoint!
Photochemistry is an enjoyable puzzle game that can quickly become complex if you overthink your solution, yet that's exactly what makes it so fun! Plus, I absolutely love the art style of the game, it's so simple yet charming.
I photocame, I photosaw, I photoconquered
Man, what a gem! I will definitely 100% complete this game. Figuring out a solution is so satisfying, and I like that there are infinitely many ways to solve a level. I wish we could see other people's solutions by clicking on their names when a level is completed, hope that'll be added soon :) First ending took me about 6 hours, but according to the achievements there is still one last act I haven't seen yet. Two slight issues I had during my playthrough: - The background is still displayed when in a puzzle, sometimes hindering visibility, especially in levels with holes. It would be nice if it was at least darkened a bit. - The acts are too difficult to find. I had to find a walkthrough online to figure out how to get to Act 2 (what looks like a wall is actually a ramp). I still haven't found Act 4 either. Finding levels isn't the interesting part of this game, especially when it takes soooo long to move around. I wish that part would be made easier. Overall, I highly recommend! :)
Photochemistry, developed and published by Thomas Horne, is a thoughtfully designed puzzle-simulation game that centers on creativity, logic, and system-based experimentation. Set in a subdued, post-apocalyptic backdrop where plant life struggles to survive due to depleted nutrients, the game frames its mechanics around rebuilding ecological stability through chemical synthesis. Rather than presenting its premise through heavy narrative exposition, it integrates the theme directly into the gameplay: players are tasked with constructing functional machines capable of transforming basic particles into complex compounds that can sustain life. This fusion of scientific abstraction and environmental recovery gives the experience a subtle sense of purpose beneath its mechanical challenges. At its heart, Photochemistry is a construction puzzle game driven by open-ended problem solving. Each level introduces a target chemical output along with a limited set of tools and inputs. Players must design a system that manipulates particles through various devices, connectors, and transformations until the required compound is successfully produced. There is rarely a single prescribed solution; instead, the game rewards experimentation and ingenuity. Multiple configurations can achieve the same result, and discovering an elegant or efficient arrangement often feels deeply satisfying. This flexibility encourages creative thinking rather than rote memorization, allowing players to develop their own approaches to increasingly complex challenges. The game’s progression is structured across a series of acts, each gradually introducing new mechanics and environmental variations. Early stages serve as tutorials for fundamental systems, while later levels demand layered solutions that combine multiple transformation processes. As new components are unlocked, the design possibilities expand, introducing additional depth without overwhelming the player all at once. Optional challenge levels further test efficiency and spatial planning, requiring tighter optimization and more intricate layouts. This measured escalation ensures that the learning curve feels deliberate and fair, fostering a sense of mastery as players become more comfortable manipulating the game’s systems. Visually, Photochemistry adopts a minimalist two-dimensional presentation that prioritizes clarity and functionality. The interface is clean and focused, ensuring that the movement of particles and the connections between components are easy to follow. Rather than distracting with elaborate graphical effects, the art style emphasizes readability, which is essential in a game centered on understanding mechanical interactions. Subtle atmospheric elements reinforce the theme of ecological restoration, but the overall aesthetic remains understated. This design choice supports the cerebral nature of the experience, keeping attention firmly on problem solving. Sound design is similarly restrained. Ambient audio and gentle background music provide a calm environment conducive to concentration. There are no dramatic crescendos or intense sound effects to interrupt the flow of experimentation. Instead, the audio complements the meditative pace of the gameplay, reinforcing its thoughtful tone. This quiet atmosphere makes Photochemistry particularly well suited for players who enjoy deliberate, focused puzzle solving without external pressure. Replayability stems from both optimization and creativity. Because levels often allow multiple viable solutions, players may return to refine their designs or attempt more efficient configurations. The inclusion of a level editor expands the game’s longevity by enabling custom puzzle creation, offering opportunities for community-driven challenges and further experimentation beyond the core campaign. Leaderboards and achievements add additional goals for those who enjoy perfecting their builds and comparing results. Ultimately, Photochemistry stands out as a niche but well-executed puzzle-simulation experience. It prioritizes intellectual engagement and creative freedom over spectacle, offering a structured yet flexible system for players who enjoy constructing solutions from the ground up. Its calm pacing, open-ended design, and thematic integration make it especially appealing to fans of logic-based games and engineering-style challenges. While it may not cater to players seeking fast action or narrative drama, it delivers a rewarding and thoughtfully crafted experience for those drawn to experimentation and systematic problem solving. Rating: 5/10
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