Lite Rules — how a game plays

The five-minute version, written to judge whether the game is fun and playable. Full rules with IDs are in the rulebook; this page hides the numbers and keeps the shape.

The pitch in one breath

Two players. Three mechs each, built from parts like a model kit. A hex board with hills, walls and three zones worth holding. Seven rounds, players alternating one mech at a time. Every shot is a handful of dice rolled on the table: did it hit, where did it land, did it punch through, how much did it do. Parts break off. Whoever holds ground and kills mechs wins the game; best of three wins the match, and you can swap one mech from your bench between games.

Before the game: the bench

You bring a roster of four mechs. Each mech is a chassis plus a head, two arms, legs and a back mount, and a pilot. Arms are the weapons: a rifle arm, a shield arm, a blade arm. Everything has a weight, and both each mech and the team of three have a weight cap, so you cannot bring three heavies.

Bigger parts are tougher and also easier to hit: the size of a part on the sprue is literally its slice of the hit table. A huge shield arm soaks shots that would have found the core.

Pilots have a faction and a specialty. Each pilot has one passive ability that only switches on if a teammate shares their faction or their specialty, and some pilots are bonded pairs who fight better within a couple of hexes of each other. Picking three pilots who all light up, while still fielding the three you want, is the roster puzzle.

If you do not want to build, four ready-made kits are a legal roster.

A game

Deploy. Roll off. Winner picks a board end. Alternate placing mechs in your three deployment rows.

Rounds. A game is at most seven rounds. Each round:

Initiative. Both players roll two dice and add their best pilot's initiative. The winner decides who activates first.
Alternate activations. You activate one mech, then your opponent activates one, until all six have acted. Nobody sits through a whole enemy turn.
Score. At the end of the round, each zone you hold (your mech inside, no enemy inside) scores a point.

Ending. Destroy all three enemy mechs and you win on the spot. Otherwise, after round seven, higher score wins: three points per kill plus the zone points you banked. Tie goes to whoever has more hull left.

An activation

Move up to your speed, then take two quick actions or one full action. You can split your movement around the actions.

Quick actions: Fire one weapon (once per activation), Boost to move again, Lock On to a target so everyone shoots it better, Brace for a point of armor, Vent heat.

Full actions: Barrage fires two weapons (and heats you up), Aimed Shot picks where a single shot lands instead of rolling for it, Overwatch holds a weapon to fire on the enemy's turn, Stabilize dumps heat and repairs a critical effect.

Terrain matters: climbing costs movement, foliage slows you and hides you, a low wall next to you is hard cover, high ground helps your aim. Standing next to an enemy makes ranged shots harder for both of you.

A shot, die by die

Hit. Roll a d20, add your pilot's gunnery and the weapon's accuracy. Situational modifiers are extra dice: bonuses and penalties cancel one for one, the survivors are rolled and the highest is added or subtracted. Beat the target's evasion.
Location. Roll a d20 on the target's silhouette. Bigger parts own more numbers. If the target is behind a low wall, a legs result hits the wall instead.
Penetration. Roll a d6, add the weapon's penetration, compare to that part's armor. Below: half damage. At or above: full. Well above: full plus a critical effect. A six always gets through.
Damage. Roll the weapon's damage dice. Take it off that part. Anything left over goes into the core.

Parts at zero are destroyed. Lose an arm, lose that weapon. Lose the legs, crawl. Lose the head, shoot blind. Lose the core, the mech is gone.

Firing builds heat. Go over your reactor's limit and you roll for stress: lose an action, lose your armor for a turn, or melt down.

A worked round, in words

Ruko's Reaver jumps four hexes onto a rooftop and opens up with its autocannon on Sato's heavy Bastion, which is crouched behind a low wall. Ruko has high ground, the target is locked by a teammate, and Ruko's own ability rewards the long move, so three bonus dice; the wall is worth two penalty dice; one bonus die survives and rolls a 2. Three shots. The first is a natural 1 and misses. The second hits and rolls "legs" — the wall eats it. The third hits the cannon arm, the d6 gets through its armor, five damage. Ruko's reactor ticks up two heat. Sato's turn.

The match

Best of three. Between games, each player may secretly swap one fielded mech for the fourth on their bench, as long as the team stays under the weight cap. The bench lets you answer what you just saw.

What should feel good, and how we will know

Every activation is a real decision. Where to stand, which weapon, whether to lock or brace, whether to push heat. If a player ever has nothing to think about, the round structure is wrong.
Dice moments are readable. The location die landing on a silhouette, the wall eating a shot, the six that punches through heavy armor. If the dice feel like a slot machine rather than a story, the modifier system is failing.
Damage tells a story. Arms gone, legs gone, a heavy limping. Players should describe fights by parts, not by hit points.
Comebacks exist. Heat is the push-your-luck lever: Barrage and Overcharge are how a losing player forces a swing.
Twenty minutes. Seven rounds of six activations. If real games run long, we cut rounds or speed the dice, not the decisions.
The build mattered. After a match, players should be able to point at a part choice that won or lost it.

The simulator in this repo already plays thousands of these games per second against itself; it tells us about the numbers. Only humans can tell us about the six bullets above. That is what the hotseat prototype is for.