GUNMETTLE - Mecha Military Scifi for the OSR

    

     Howdy. It's been a minute since I last posted, huh? 2025 was definitely a hell of a year, quite possibly one of the years of all time, but 2026 so far has definitely been giving it a run for its money. Since I last posted, my projects have been moving along. Kharon is still kind of on. No Zaku's getting more development. But, my dabbling into the OSR has had my head buzzing with ideas for months, and especially with the harder end of science fiction reappearing in the obsession cycle, those ideas have taken on that shape. I wanted to make an OSR game.

    It got me thinking about a setting I'd worked a little on, and abandoned, since the friend it was made for lost interest in using it. It had a lot of interesting ideas taken from your less "woo-woo space opera" kind of scifi. When I was first writing it up, I had thoughts of Gundam (Universal Century and Iron-Blooded Orphans; y'know, the actually good ones), VOTOMs and Armor Hunter Mellowlink, Dougram, Gasaraki, maybe even Code Geass when it's not being lame and gay; mecha that move like big infantrymen, perhaps sometimes with a jetpack. That got me thinking about Battletech, the technical specificity of it. And then on top of that, other miscellaneous things out of the grab-bag, like Starship Troopers (the novel, not the movie that butchered it), Cyberpunk 2020, Deus Ex, Metal Gear Solid, even Call of Duty: Advanced Warfare of all things. And the last spice was thoughts of Cold War geopolitics and history; the golden age of the Mercenary, proxy wars like Angola, figures like Neall Ellis. It all metastasized into my new project; GUNMETTLE.

    GUNMETTLE is set in the year 2983, by which mankind has invented FTL multiple times now, mastered terraforming, and has settled thousands of worlds in a 250 lightyear radius around Sol. The great powers wage the same proxy conflicts that hegemons have since the 20th century, fighting to capture the hearts, minds, and loyalties of the thousands of independent peripheral powers, locked in a paranoid power struggle to ensure the continuation of their ideologies. A so-far uninhabited galaxy, flush with resources, infinite space and materiel to move past scarcity, instead leveraged towards a grander scale of political competition than any nation of old Terra could have possibly imagined.

    The basic mechanics will be overall familiar to anyone who's played D&D, as this system is (nominally) OSR-strict (See Socratic's two-parter treatise on the subject, here, and here). It uses the familiar core-six attributes, being Strength, Dexterity, Constitution, Wisdom, Intelligence, and Charisma. Checks are all done on a d20, bigger number is better, etc.

    True to my taste in design though, I've bolted on some very in depth subsystems to go along with the OSR basics. For starters, I've always loathed Stat Stick™ weapon design, particularly where it pertains to firearms, which often end up as reskinned crossbows. I happen to be something of a gun enthusiast, and I can say that every gun handles a little different. Some point very naturally, some suck to hold. Some are very controllable, and some beat the hell out of you. Some are deceptively light, and some deceptively heavy. And what's not immediately obvious to anyone who's not gotten hands on with a lot of guns, is that two models that are broadly comparable on paper can differ greatly in this way; take for instance, a bog standard AR-15, and a Mini-14, which are both nominally .223/5.56mm gas operated rifles, yet feel entirely unalike in their handling. Just how do you reflect the sheer variety of guns, with all of their little quirks and considerations, in a TTRPG?

    My solution is treating a gun as a bag of traits. Any given gun has a multitude of keywords, and every keyword has its own mechanics. For example; automatic machine guns, semi-automatic guns, burst firing guns, pump actions, and far more than just that, all behave and play differently, playing off different strengths of the wielder; some determine number of shots and valid targets by different stats, some have gimmicks that require checks, so on and so forth. Then add onto that more specific keywords that tweak things around, and suddenly you can model a wide range of guns faithfully to their real handling characteristics.

    And anyone who knows guns, say someone who's done a lot of hunting, or a combat vet who's seen it up close, or even just a ballistic gelatin enthusiast, will know that what a bullet does to somebody, is not the same as what an explosion does to somebody, as what a knife does to somebody, so on and so forth. To this end, another subsystem; injuries. The short version is that if you hit zero HP, you roll the table for the damage type that put you down, and then there's an entire rich, detailed triage and surgery system. I can say from playtests, that this is excellent at driving tension and drama at the table.

    And then the mechs, called Vertical Armors in this system and setting, are another very big subsystem. You're having to weigh power consumption, heat generation and cooling, and what kinds of weapons can and can't deal appreciable damage to your VA. While the mechanics are similar to infantry scale combat, they've felt qualitatively different in playtests, which is more than I could've hoped for.

    Another small thing I've sought to tackle is my dissatisfaction with exceptional, heroic narratives in TTRPGs. It seems everywhere you look, there's some purported mud farmer with a +2 magic sword, who is, according to the rules as written, able to tank a direct meteor strike without significant trouble. I wanted something that feels desperate, life-or-death, requiring you to be scrappy and resourceful to make it to the finish line on your first character. To this end, I've opted for a classless, no-level system where the sole determinants are the equipment you've been able to buy, and how your skills have evolved over time. This particularly, has been very effective.

    There's still so much more to do, but it's been very promising so far. I've had a good group to playtest this with, and development is moving apace. More articles will follow, going over the discrete mechanical subsystems, aspects of the lore, and more, but in closing; this will be a game that demands sensible tactics, shrewd resource use, and some amount of luck to scrape by in, hopefully producing some memorable emergent narratives throughout. I have high hopes.