That's a lot of Zombies

Up to 100,000 zombies at once. They all want your roof.
You're the gunner on an AC-130. On thermal the living glow white and the dead show black. Hot ones are ours. Cold ones aren't.
Man the guns

Hose the crowd with the 25 mm and save the 105 for the thickest part. The whole airframe kicks every time it fires. There are eight big guns to unlock, napalm included, and you take one up each night.
Keep them off the roof

The dead stack up every wall of the building to get at your squad. Knocking a pile down means shooting right next to your own guys.
Your squad fights back. Give them snipers, a machine gun team and claymores.
Rig the streets

Before each night you set the streets up your way. Roadblocks steer the dead where you want them, a dozer shoves the piles flat and sentry guns hold a flank. The killing is still yours.
Call in the big stuff

Call in A-10 gun runs, B-52 bomb lines and a B-2 that bombs every pile around your roof. Bring three a night.
Get through fourteen nights

Fourteen nights in places like a frozen dam, a rail yard and a stadium full of the dead. Each one sends more of them, and each has its own trap. Shoot the ice out from under them, drop a tower across the avenue or let the rail cars loose down the yard.
Lose a night and you still get paid. Upgrade and go again. There's a Daily Challenge too, and a Last Stand where no helicopter comes.
Every night you win ends the same way. The nuke goes off as your squad flies out.