Bunker Siege

One bunker, one hill, and a meadow they keep crossing. Riflemen and grenadiers first, then troop transports, tanks, gunships, a bomber spilling paratroopers out of the grey, dug-in howitzers, and a jet that walks cannon fire up the slope. Every dollar is banked before you fall. Death resets the rounds — your wallet, your guns and the bunker you paid for survive it. Every run starts stronger than the last. A chain of weapons from a six-shooter to a belt-fed machine gun. Each one has to be fielded before the next unlocks. Hired riflemen who work the wall beside you, carry the guns you buy them, and are back at their posts next round if they fall. Bunker work: thicker concrete, a rocket rack on the parapet, a radio to the battery behind the hill. You will not always see them coming
Night is black and fog is a wall, and whatever is inside it closes to knife range. Throw a parachute flare and the field burns white.  Two campaigns:
Green summer, or a field buried under snow that never stops falling.