Your base is under attack! Get your best chopper out there immediately and demolish every enemy unit on sight. Don't forget to build towers and repair damaged towers to help accomplish your mission.
Use towers to build a labyrinth from entrance to exit. Each tower can be upgraded 4 times. With each wave, enemies will become stronger, so use money you earned to upgrade reasonably.
Use powerful trap combination to send your pirate enemies through a whirlwind of pain, as well as earn you big gold rewards and points! Can you stop the pirate waves from reaching the top of the screen?