Glacis

One corridor, three generations
The corridor is attacked three times, thirty years apart, and each time the North brings a new way of fighting. First come long-range guns, dive bombers and paratroopers. A generation later, self-propelled guns fire and move before you can answer, helicopters set infantry down away from the road, and in the mountains the rivers freeze hard enough to drive on. A generation after that, it's drone swarms, camouflaged vehicles and incoming missiles you can only stop with interceptors you have to ration. Every one that comes in is a decision. Each generation of defenders inherits the last one's weapons and has to find answers of its own.You can't block the road
The battlefields are shaped from real terrain — valleys and ridges, rivers and coastline, snowbound mountains and desert shores — and the enemy will always find a way across them.

You can't stop them with a wall. What your engineers can do is move the earth. Raise the ground and the road bends; a longer road keeps the enemy under your guns for longer. Each kind of unit reads the land differently: infantry walk straight over a rise that sends trucks the long way round.Height decides the fight
Most weapons reach farther the higher they stand, and a hill hides everything behind it from direct fire. Mortars and rocket launchers drop shells over the ridge, but can't hit what's too close. Where you dig in matters as much as what you build.Two things to hold
Tanks drive for your base. Everything else on the ground heads for the landmark — a church or a lighthouse in the first war, a dam or a hospital in the second, a port in the third. Lose either one and the battle is lost. Keep both standing and the lab gets more to work with.Winter, desert and the sea
In the second war the fighting climbs into the northern mountains, already deep in snow, where frozen rivers become roads. The third war reaches a desert coast far to the west. In between, the allies call you to their own ground: tundra, estuaries, islands and highlands.Night, and the sky
After dark, your AA guns do only a third of their damage to aircraft they can't see — unless searchlights and flares light them up, or radar guides the guns. Paratroopers drop, gliders land, half-tracks let infantry out where they stop, and dive bombers go straight for the landmark. Later wars bring night jets, decoy flares and helicopter assaults, and the answers change with them. When it gets bad, call in air support.The lab
Clearing operations earns research points in Materials, Chemistry, Electronics and Manpower. A weapon unlocks only when every technology it needs is in place, and there are never enough points for everything. What reaches the front is your call.Answer the allies
The same four allies — the Tundra, the Estuary, the Archipelago and the Highlands — ask for help in every generation, and what they send back changes with the times. Their expeditions pay in research, captured equipment and air support. Some requests come in pairs, and whichever you answer second starts at a disadvantage.Features
Three acts and 80 battlefields: one corridor held by three generations, from 1940s guns to 21st-century drone swarms

Tower defense over real terrain — raise the ground, bend the enemy's road, take the high ground

Two objectives in every battle: your base and the landmark

A new enemy every generation: helicopter assaults, amphibious landings, airdropped vehicles and drone swarms

Snowbound mountains, frozen rivers, desert coasts and islands, by day and by night

A research lab that moves with the eras, where weapons grow through three ranks

Voiced radio reports from your staff