Tower defence game. You can build towers on Islands and destroy the incoming ships before they destroy your Command Tower. The ships can fire back so watch out, strategically place your towers, use shield tower to increase defence and radar tower to increase radius of Cannons, Flak Turrets and Artillery.
You can choose to play on Ship Side. Organize first wave with ships that are available and set delay time. As long as you are destroying towers you gain resources and you can send more ships. Your goal is to destroy Command Tower.