The ship features a regenerative shield capable of absorbing enemy bullets, but with overuse can deteriorate.

There is a unique timing score utilized in each game (Eschatos, Judgment Silversword and Cardinal Sins): a timer is set to count up with every enemy wave and boss encounter.

Eschatos takes place in the 22nd century where a mysterious organic alien matter - known only as the Purple Erosion - has taken over The Moon.

After covering 75% of The Moon's surface, the aliens launch an attack on the Earth using flying saucers to deploy trajectory weapons and ships.

The player is tasked with stopping the invasion using a fighter ship capable of great attack and defense technology.