Walkthrough: Deploy all riflemen on one side of the beach of your choosing to engage the Boom Cannons. They should be able to fire upon them without being in range of the Rocket Launchers. Keep flaring your riflemen to the beach in order to stay out of range and allow them to take out 3-4 Boom Cannons. Your riflemen will inevitably die out, but by then they would have accomplished their job. Deploy the rest of your units on the beach, but make sure to Shock Bomb the remaining Boom Cannons to prevent them from firing at your units. Either flare your Tanks to the opposite side to avoid the Boom Cannons, or alternatively you can have your Tanks take them out with the help of some more Shock Bombs. Afterwards, let your tanks destroy the Storage Buildings to clear a path to the Headquarters. Use the accumulating Gunboat Energy to take down the two Shock Launchers. By this point, your biggest enemy is time. Attack the HQ with your tanks to win the battle.