Iron Protocol
A hex-grid tabletop wargame of heavy mechanical combat, set in a hard science-fiction world that had to argue for its own existence — and whose answers became its rules.
Current edition 2026-08-13 — printed on the rulebook cover and every sheet, so you can always tell how current your copy is.
Secure a sensor lock and the shot connects. There is no to-hit number anywhere in the rules, so no shot is ever wasted on a bad accuracy roll. What you are fighting over is not whether you hit — it is whether you can see.
Visual, Infrared and Radar — and every weapon needs one of them. Woods, buildings and elevation deny a band outright; chaff, smoke, jammers and an adaptive skin only contest it, on a single die roll that is the same number for every defensive system in the game. Blind a Frame on the band its gun is slaved to and it is carrying dead weight, however much energy it has left.
Spend almost nothing and infrared has nothing to find. Not a saving throw — a hard block, because there is no heat signature to contest. Stealth is a choice about how little you are willing to do with your turn, and an assault chassis is too big to make it.
Damage must beat the plate, or it does nothing at all. There are no hit points. A penetrating hit strips one point of armor permanently, so a Frame is progressively opened up rather than whittled down — and an autocannon cannot scratch an assault chassis until something heavier has opened it.
Slow Frames move first and shoot last. They commit to a position blind, then watch the fast ones fire before they can answer. Scouts move last and shoot first. That single inversion is the spine of every decision on the board.
Walking costs it. Firing costs it. Hiding costs it every round. Bank charge in the capacitor for an overcharged rail gun, or spend it sprinting for cover — but the same reserve pays for both, and it never stretches.
Most mecha settings ask you to take the machines on faith. This one argues for them, and the argument is what generates the rules you play.
A runaway debris cascade — the Kessler Shroud — shredded everything in low orbit and never thinned. No GPS. No reconnaissance satellites. Ballistic warheads are stripped apart before they reach apogee. Humanity effectively walled itself out of space, and battlefield intelligence collapsed back to line of sight.
With nothing overhead, a pilot knows only what their own optics, thermal imagers and radar can find. That is exactly why the rules are built on three short-range bands — the electronic warfare layer is not a subsystem bolted on, it is what is left of reconnaissance.
The Cinder Wars burned the fossil reserves, and a single jet sortie now consumes a faction's monthly stockpile of refined propellant. Fusion-powered Frames run for months on hydrogen isotopes — and unlike an aircraft, they can hold ground.
Duels between champions collapsed within a generation: leaders sent proxies and disavowed them. A Frame is different — rare materials, years of fabrication, a pilot whose neural link took a decade to calibrate. Losing one is a wound a faction feels for years.
A 1v1 mirror match between two Vanguards, in Section 1.4.1 of the rulebook. Identical Frames mean every difference in the outcome comes from your decisions rather than the matchup — which is the fastest way to learn what the energy economy is actually asking of you.