From Wizard's Lab:
Net War is a fun, easy to learn game that blends modern high-resolution graphics with the addictive gameplay of classic arcade games. You are a network security agent who is protecting data banks from hackers. On each level there are three data banks set in a computer grid that you need to protect. As wave after wave of hackers invades your system, racing down through paths in the grid you must stop them by dropping black ice bombs on the path in front of them. As you progress through the levels the arrangement of the databanks will change, presenting more and more challenging scenarios with each level. Also the hackers start spawning faster, and more hacker types with new behaviors appear.