Survive as long as possible by building the most efficient line of defense. Eliminate the bad guys from attacking your home base. There are also several different game modes available.
Keep your base safe from the huge advancing army using your trusty sniper rifle, air strikes and artillery. With each wave the invading army gets stronger, spend your money on the right upgrades and try to survive the war!
Protect the flora against the invading monsters by building your army of plants. Design your own path with defense units. Juggle the exit gates to confuse the incoming monsters.