Defend your PC from the viruses attack. Use Norton to shoot in 1 direction, 100% damage for all viruses, Nod32 shoots in 8 directions, small damage but fast, Mcafee shoots in 4 directions, medium damage, Antivir slows down viruses, no damage, Avg, huge damage to all viruses in its range, Kaspersky throws viruses back. There are also different kind of viruses with different qualities.