Spira Defence for Android is a tower defense with a twist. You must defend your base from an incessant enemy attack. Money is awarded for kills and interest is earned on the money left in the bank at the end of a level. Space to build towers is severely limited, but the towers themselves are almost infinitely upgradeable.

Spira Defence for Android is a tower defense with a twist. You must defend your base from an incessant enemy attack. Money is awarded for kills and interest is earned on the money left in the bank at the end of a level. Space to build towers is severely limited, but the towers themselves are almost infinitely upgradeable.