Battle to survive the strong waves of viruses. Strategically deploy the defenders at right time on right position. This game has 3 different weather conditions. Try to survive by killing all the viruses in limited time period. If you stop deploying even for a second, viruses will jump on you and kill you. There are various catagories of viruses with their ability to dodge the obstacles in the way and in some cases destroy the obstacles too. be aware of Red colour spiky, don't let him come close to defenders. if you will be able to survive upto level 9 which means you've killed all the viruses on earth. but don't be happy there are still some viruses are left on Mars, later you will be directed to mars by spaceship. Viruses on mars has some special ability and they are way more dangerous than earth viruses so be fast and precise in deploying the defenders. In last have fun.