In the winter of 2012, I was unemployed and living in a tiny apartment in Greenbelt, Maryland. When I started feeling the unmistakable scratchy-throat tingle of a new cold, I decided it was the perfect time to crack open a game that had been on my radar for a while and was generating all kinds of indie buzz: the kickstarter success-story FTL. Over the course of a dreamlike week, I logged more than 40 hours of play. (Who needs a job?) Now, in 2021, I still count it as one of my all-time favorite games.

I knew that FTL was a founderwork which would spawn a genre—not of “sci-fi ship vs. ship battle games”, but of a certain kind of board-gamey, strategic videogame in general. In 2014 I tweeted:

A few years later, Slay the Spire became a massive indie success. I'm approaching 1000 hours of play, and I love it even more than I love FTL. Other games in this vein have popped up like mushrooms—Into the Breach, Dicey Dungeons, Monster Train, Griftlands. It’s a thing.

We don’t have a great name for this thing. The above games are often classified as “roguelikes”, but the term is highly contentious, and in any case, I want a sub-term that specifically refers to games like FTL and Slay The Spire, as opposed to Nethack and Spelunky. “Roguelike deckbuilder” is a thing, but I’ve never heard anyone refer to FTL or Into the Breach as deckbuilders. With a hubris typical of all game designers, I propose a new term: serial strategy.

Serial Strategy Defined

A serial strategy game is a run-based, procedural, short, single-player videogame in which a single run consists of a strategic core game played many times in a row and embedded in a build-based overgame.

Run-based—The game is designed to be played over and over again.

Procedural—Every run is different.

Short—A single run can be played in one sitting. One hour seems to be the evolving standard, analogous to the 90 minute standard in film.

Single-player (or co-op)—The primary “opponent” is a system or an environment. These systems and environments tend to be algorithmically transparent, but often exhibit complex emergent behavior.

Strategic—The primary focus is on skillful thinking and planning, as opposed to dexterity-based execution or undirected exploration.

Core game—A strategic sub-module which has a beginning, middle, and end. It tends to last somewhere between five seconds and five minutes. One can imagine a modified version of the core game as a short stand-alone game.

Build-based—Over the course of a single run you gradually develop a unique “build” of characteristics, abilities, and/or items. The uniqueness stems from the fact that during any given run you’ll only encounter a random subset of the possible build elements, and you’ll only acquire a subset of that subset. These elements tend to be less like numerical stats and more like discrete special powers that synergize with each other and the game’s environment in complex and surprising ways. Details of the build can dramatically affect the play of the core game during a particular run.

Overgame—This refers to all of the gameplay that happens during a run that’s outside of the core game. The overgame is supplementary. A run is always heading toward a final instance of the core game, and every overgame decision directly or indirectly affects that final instance (or increases or decreases the chances of reaching it).

Note that "overgame" is not equivalent to "metagame". The overgame happens over the course of a single run, and it ends when the run ends. The term "metagame" can be used to refer to gameplay or permanent progression that occurs between runs. My definition of serial strategy is metagame-neutral. Inter-run state-change may be elaborate, minimal, or non-existent.

Winning and Losing

Although it isn’t strictly necessary, most existing serial strategy games are winnable, losable, and irrevocable.

Winnable—Since a run consists of a series of core game instances, logically there must be a final one. The goal is to reach it and win it, whatever that means in the context of that particular design. Scores are secondary, or non-existent.

Losable—It’s possible for a run to prematurely terminate in failure.

Irrevocable—You live with your decisions. Many games provide some form of undo or reload, but it’s usually limited.

This overall structure reliably ties a series of core instances together into a compelling whole. However, its punishing nature threatens to relegate the genre to a niche. My definition of “serial strategy” does not mandate this particular goal structure (although of course it allows for it). We can imagine a serial strategy game in which you are guaranteed to reach the final instance, and in which your chances of winning that instance are dictated by how well you did in all of the previous ones. Or we can imagine that you don’t win or lose the final instance, but simply finish it and receive a score or a star-rating. Time will tell whether such alternatives have wide appeal, or are even compelling enough to be viable. The genre is young. Experimentation is in order.

Further Thoughts

I’m a videogame designer at heart, but I cut my teeth on tabletop Eurogame design in the early 2000s, which resulted in things like Zendo and Blockers (neither of which is very Eurogame-y, but let that pass). Those experiences have shaped my current perspective, and inform my excitement about the serial strategy genre.

It’s surprisingly difficult to find an outlet for Euro-style game-mechanical design in videogames—especially single-player ones. We have genres like grand strategy, 4X, real-time strategy, tower defense, MOBA, CCG, auto battler, and turn-based tactics. These are a bad fit, for multiple reasons (not the least of which is the heavy focus on combat). We have indie “casual puzzle” games like Threes, Drop7, and Triple Town. Those are closer to what I’m looking for, but they exist within a narrow space. I love Mini Metro and the recently-released Slipways, but they feel like one-offs that don’t clearly establish a framework for future design. I can count on a few hands all of the good single-player strategy videogames that exhibit that elusive "Eurogame flavor". In contrast, there are hundreds of actual Eurogames published every single year.

The serial strategy structure can function as a delivery system for Euro-style mechanics in single-player videogame design. Slay the Spire—the most successful serial strategy game so far—lifts its central card-play system right out of Dominion. I believe that there are structural and systemic reasons why the above-outlined serial strategy structure is such a good fit for these kinds of mechanics.

If I’m right about all of this, the next step in the evolution of the genre will be to expand outward into the space of non-combat games. Nothing in my definition of “serial strategy” dictates that these games have to be about combat. Eurogames themselves almost never are. Design space is full of beautiful and fascinating mechanics that have nothing to do with reducing hit points to zero. I don’t have a moral problem with games about killing monsters, but I do think it’s a shame that our new genre is (so far) ignoring vast swaths of design space. And, although I can't prove it, I suspect that there's a broad audience of players who would enjoy playing games that are "like" FTL or Slay the Spire, but in which you're settling islands, or planning routes, or placing workers, or collecting sets, or doing one of the thousands of other fun things there are to do in strategy games besides killing monsters.

My aim is to explore the theory and practice of serial strategy game design (particularly of the non-combat variety), and to convince other designers to start exploring it with me. I’m interested in questions like:

I’ll continue to explore such questions in future essays and videos. I also plan to put my money where my mouth is. After nearly a decade of poverty and cowardice, I’ve scraped together enough cash (and gumption) to allow me to devote myself full-time to the design and production of one of these games. And—with some trepidation—I’ve decided to develop the whole thing in full view of the public. I’ll be making prototypes to test my theories, and they’ll be freely available to all who are interested. Follow me, and join the conversation!

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