July 14, 2520 AD.

The human race was annihilated by the light emitted by the "stone-like object" excavated from the stratum before Christ. Only four crew members belonging to the space cruiser "TETRA" and one robonoid survived in satellite orbit.

A year later. The supplies on board are depleted.

TETRA is forced to re-enter the atmosphere and begin the fight for human survival.

Stages with various topography such as intricate gaps and moving containers become battlefields, and enemies attack from all directions, up, down, left and right. And 23 bosses await beyond... 6 highly challenging stages await you.
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Use different weapons that level up by earning points and beat the high score!