Earth is threatened by an alien species, the Ne'ahtu. Early in the twenty second century, the Ne'ahtu infected Earth's energy grid with a computer virus that disabled the planet's defenses. Before the Ne'ahtu could strike, computer prodigy Amy Ramanujan neutralized the alien computer virus and saved the planet. Now, the Ne'ahtu are back and Dr. Ramanujan is trying to prevent another all-out invasion of Earth. Switching between towers (to launch missiles and mortars) and face-to-face combat (to attack with machine guns), the player's mission is to join Dr. Ramanujan and defend Earth from the Ne'ahtu. (Dual Mode Gameplay) Bring friends and family into the action with the Sev Zero companion tablet app, Sev Zero: Air Support for Kindle Fire. With this multi-player, multi-screen experience, a friend can help you repel the invasion by firing missiles, freezing enemies, and deploying explosive decoys from their Kindle Fire tablet while playing alongside the game on Amazon Fire TV. Download Sev Zero: Air Support to your Kindle Fire tablet now.