The dead are coming in waves, and every wave is bigger than the last. Train a squad, wall off the approaches, and keep the HQ standing for as long as you can.
Drag / clickSelect (Shift adds, double-click picks a type)Right-clickMove selected units around obstacles1–9Train units or build (Tab switches Squad / Base)Z X C VAirstrike, Artillery, Supply Drop, ParatroopersRRotate barricade (drag to lay a line)WASD / wheelPan and zoom the cameraQ · Space · PSelect all · Jump to HQ · Pause