Why have I only found my new favourite puzzle developer shortly after they announce they're finishing?

This is my second Zachtronics game after Opus Magnum. On the surface, the games may seem quite similar; both are programming-puzzle games in which you give instructions to a machine to produce a defined output based on some input. In each case you will end up struggling for space as the machines become more dense, and you compete with yourself and others in terms of speed and complexity of your machine. But the actual core of these puzzles could barely be more different.

In Opus Magnum the machines are fairly abstract with a vague 'chemistry' framework. But in TIS-100 you are solving actual real-world problems with a very limited set of instructions. Can you sort this list of numbers just by shuffling them between stacks? Can you print this vertical histogram by only printing horizontal lines? I love it; the puzzles feels so much more meaningful than they did in Opus.

And yet, I do still think Opus Magnum is the significantly better game. It's undeniably much more polished, and does a better job of explaining its mechanics to the player (TIS-100 literally just redirects you to a PDF file for a list of commands if you dare to ask it for help). And I really did miss the almost tactile feedback in Opus; the sound design and visuals in that game were fantastic with your machine clanging along to a rhythm as it worked, while TIS-100 is visually extremely minimalist and almost completely silent. I know it's only a minor thing, but I think a few more beeps and computery sounds as each node went about its tasks would make this a lot more engaging.

But yeah, very solid puzzle game. Just be aware that the barrier to entry can be a little high, especially if you are lacking programming experience.

While known for its more applied problem-oriented puzzle games, Zachtronics offers a more abstract experience here, embracing the language of assembly. TIS-100 takes its name from the eponymous computer, whose architecture resembles the devices of the 1980s. The core of the game consists of reading a series of inputs and solving a specific statement, which creates a sequence of outputs. The commands at our disposal are simple operations of moving between nodes and in two registers (the accumulator ACC and the reserve BAK). Being a low-level language, the title allows itself a rather pleasant progression curve: a programmer audience will obviously be at an advantage, but everyone can try the experience. The minimalism of the game is thought-provoking and a certain serious atmosphere emerges from this dryness. The succinctness of the statements and commands available forces one to spend a lot of time on one's notebook, in order to start thinking ahout theoretical approaches. Such a title cannot therefore please everyone, but it has a formidable quality in its progression curve (Sequence Sorter and Sequence Mode Calculator are particularly devious, however): from there, a didactic approach emerges, allowing epiphanies and joys in solving increasingly difficult problems. It is worth mentioning the existence of a narrative framework, which gives context to what the TIS-100 is, without polluting the pace of thought. Ultimately, TIS-100 is a very solid first attempt at pure programming, which SHENZHEN I/O and EXAPUNKS will refine.

I usually think of myself as a very intelligent person with a natural talent for solving problems and the analytical chops to make these solutions work within a given framework, but Sequence Sorter had other ideas. Sometimes I tell myself I'll get it done one of these days, but the last time I gave it a go I fell one or two additional lines of space short of unclogging an unholy abomination that got about halfway through before it needed yet another ugly, unwieldy hack to keep going, and I think I never felt so crushed while playing a video game - elsewhere you might get a game over, but TIS-100 will defeat you.

I've been a zachtronics fan since I stumbled across spacechem in 2014- since I was 11 years old. I was following each release with extreme excitement, well before they became the king of the engineering niche, well before I could even truly appreciate these games.

It wasn't until 2018 that I even meaningfully played through a whole zachtronics game-by finishing opus magnum. Until then I had played about 4/9 of spacechem, the first few levels of infinfactory, the first row or two of tis100 levels, and maybe I opened shenzhen I/O once or twice. I loved Zachtronics games, but I knew I had not truly gotten into them

Tis100 is the game that I orginally bounced off the hardest

12 year old me wasn't a fan of having to read a manual. I remember looking up a youtube video for a guide on what every instruction did. Even after having done that, i pretty quickly ran into a level that I was simply stuck on. This game wasn't my first exposure to programming, a life passion for developing games took care of that, but it was my first encounter with assembly programming. More importantly, it was my first encounter with what it's like to actually do problem solving as a programmer... too hard for someone who was unknowingly trapped in the unhelpful hell of following along with game dev tutorials

Now let's jump ahead to 2022. Tis100 is the first of the Zachtronics programming games that I actually got into. I was finally determined to start tackling my backlog of Zachtronics games- especially the assembly programming trilogy.

8 years changes your perspective on a game a lot. Somewhere in that time I crossed the arbitrary line where I considered myself a real programmer. Reading documentation is no longer a scary devil... I'd take it any day over watching a YouTube video. I'm also an adult now, that's probably the most important one.

Tis100 was surprise launched, marketed as the assembly programming game that no one asked for. Now, it's one of the few games that exists in one of my favorite genres. I am now the person who asks for assembly programming games. Shenzhen I/O and EXAPUNKS are both in my top 5 games of all time. Tis100 isn't quite as good as those games, but it is still fantastic
It's hard to stop myself from writing a 1 sentence review for any of the games in this "trilogy" -> "Zachtronics programming game: 10/10". That review would undersell the game. I like to think of tis100, shenzhen i/o and exapunks as siblings. Any parent could tell you how different they are, even when it's obvious how much they have in common

In many ways, Tis100 simply suffers from being the oldest child. I want to say tis100 walked, so the next 2 programming games could run- but this would be unfair to tis100. You see, even as the rough first attempt at an assembly programming game, tis100 has a distinct identity. It is without a doubt some people's favorites Zachtronics game

That says a lot given how minimal this game is. You get no music, barely any narrative, no neat little side solitaire, a simple presentation, and a severly lacking UX . These are all things that other games include which make them automatically enjoyable- Tis100 does not believe in free lunch, you have to put in the work

This is the soul of the game. You have to work to do even the simplest things. Every single instruction in this language is designed to be annoying. You must fight this strange architecture every step of the way. Your hopes and dreams will constantly be shattered by the unceasing pain of all your limitations

The Tis100 operating system is truly cursed.
Yet the beautiful part of this game is the process of growing to understand it. Its quirks become natural. Behind all these limitations is a terrifying power...

The obtuse manual is hiding incredible epiphanies. Play this game for long enough, and you'll develop an arsenal of cursed techniques

There's a lot of potential to unlock with the power you are given. There's things you can do in tis100 that i found myself wishing I could do in Shenzhen and exapunks- despite how those games have much more powerful languages. I'm still not sure I've mastered the depths of tis100's darkness.

Tis100 absolutely nails the fantasy of learning to love a strange and obscure architecture. This isn't just a game about solving abstract problems in assembly... this node based enviornment is unlike any other programming i've done, and my journey with it has been incredibly rewarding.

I'm not sure I've spent enough time emphasizing how interesting Tis100's challenges are to me. Something about the abstract way you're manipulating data here simply vibes with me. There are very few games I've "gotten into" the same way I did for tis100, and games are my greatest love.

Even at the point of writing this review, tis100 will still be a game I occasionially revisit. I have plenty of evil bonus levels waiting for me, and of course I can always go back and try to optimize

Cycles optimization is very fun, and it's the metric that naturally interests me the most. Often it's about finding a clever algorithm or approach, rather than just using efficient techniques. It's a little disapointing how often "optimal" means hard-coding things, but that also fits well.

Node and size optimization feel slightly adjacent on the surface, but once you dig into one it becomes distinct. Pursuring these metrics is a great way to embark on the wonderful journey of cursed techniques. I mostly ignored these metrics for a lot my playthrough, but they're more interesting to me now


The best feature of the game is the friend leaderboards. Its what makes this layer of the game shine. It's fun to compare yourself after you finish a level, and it's a great motivation to pursue optimizations.

There are very few video game levels I despise. Sequence Sorter is one of them. The only thing i hate more than sequence sorter is dicey dungeon's witch elimination round.
I dropped the game for a year because of this level. Occasionially throughout 2022, i reattempted this level and just miserably made no progress. It is only now at the end of 2023, that one of these desperate attempts actually crossed the line into solving the level. Between getting stuck on this level and beating it, i played the entire main campaigns of shenzhen i/o and exapunks.

The thing about tis100, is that it has a ceiling for how complex the task can be for solving it to remain fun. Most of the levels in the main campaign are good at this balance. Sequence sorter is so far above it that it makes for a miserable experience, one that to me doesn't play to the strengths of the game.

Of all the zachtronics games where i've gotten to the bonus campaign, tis100's is the one that interests me the least.


Another place where sequence sorter sucks is the node placement. The stacks are just placed in frustrating spots. I'm overall not a fan of the difficulty tis100 creates from its level layouts, i much prefer the approaches of literally every other zachtronics game in this regard. Usually constraints = fun, but these constraints miss the mark.

The stupidest thing in tis100 is the horizontal character limits for each line.
I can't fit the labels i want to use to describe things and it's so frustrating.
Everytime i have to shorten my labels so i can fit a direction which takes more characters (like right), a part of myself screams in agony

Commenting in tis100 is a fool's errand, you simply don't have the space for it. This makes revisiting levels worse, solving in multiple sessions worse, sharing solutions with others worse, and generally makes my experience more annoying.
There's no interesting design constraint here like many of the "annoying" bits of tis100. It's just a UX limitation that is needlessly painful

As a programmer and engineer, this is a hard review to write.

This game is the closest I've come to doing work for fun. It puts a twist and turn on programming(assembly programming, reviled as the worst kind by most of the world) that isn't seen anywhere in the real world, yet still employs much of the concepts and basics of assembly. This results in a highly unique and stylized experience unlike anything real not like any other game(that I've experienced or heard of, at least).

As such, this is a truly remarkable little jaunt. I imagine it would be fairly hard for anyone with truly zero programming experience to jump into, yet, I also feel like anyone with real programming experience puts themselves at a deficit due to approaches and habits that are antithetical to what's required to beat the levels.

I love this game. It's not for everyone, in fact, I'd say this game likely has an incredibly small target audience. If you know any programming, I think you should try this. It may seem like a drag to do work for fun, but I think it transcends nicely. If you don't know any code but love puzzles or riddles, you should also try this. I think it provides a wonderful and unique spatial and temporal thinking challenge,

Possibly my least favorite Zachtronic puzzle game so far. It has all the claustrophobic space constraints of Spacechem without any of the visual excitement. The commitment to the bit, while laudable, really hampers to UI and debuggability of the game. While of course the programming language needs to be constrained to actually allow for puzzles, it (much more than, say, Exapunks) makes anything even moderately complex feel like a slog. By the time I got to the end, I no longer had it in me to put effort into optimization on any axis, which is a bit of a shame because when I'm in the flow I really do love coming up with galaxy brain solutions to these things.