Play as a war general to stop a giant monster from destroying cities. Deploy tanks, helicopters, bombers, and launch missiles to kill the monster. There are five monsters to fight: Godzilla, King Kong, giant wasp, etc.
With auto drop enabled, you can just click on the troop icons to deploy them. Without auto drop, you will have to drag-and-drop the troops to the play screen; not too convenient maybe, but you'll have more freedom to set your troops.