U N Defense Force: Earth Joker is a vertical-scrolling shoot ’em up released in 1993 by Visco Games for the Arcade. Set in the year 2026, you take on the role of a united Earth military launching a counter-offensive to reclaim the planet from an invading alien force known as the Slytow. The game features four distinct pilotable ships, each with its own unique weapon patterns, offering variety in how you approach the challenging stages.
How to Play
Your objective is to pilot your chosen ship through enemy territory, surviving waves of alien attacks and defeating powerful bosses to reclaim Earth. In the browser, the standard Arcade controls are mapped to the Arrow Keys for movement, Z or X to fire, Shift to insert a coin, and Enter to start.
Tips
- Manage your charge attack: You can unleash a powerful secondary burst attack by holding down the fire button, but doing so prevents you from firing your standard weapon. Only charge when you have a safe opening.
- Test the ships: Since each of the four ships has a completely different weapon spread, try them all to see which firing pattern works best for surviving the game’s steep difficulty spikes.

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