Planet Smashers is a vertically scrolling shooter similar to Xevious. Power ups can be captured by destroying cargo ships. Power ups include improved weapons, shield restoration, and cloaking ability. Cargo ships also drop warp capsules that the player needs to collect in order to proceed to the level boss.
The Earth Shield is a unique feature of this game, where every time the player lets a ship go by unscathed, the shield depletes slightly. If the shield is destroyed, it's game over.