The game consists of 45 levels, and no background story or plot is given. The player controls a ship called the FX-1, and collects power-up parts (called a "wing") to progress through the levels and ultimately defeat the armored mobile fortress in the final level. The game consists of two different top-view screen levels, where the player can press the second button to descend to the ground whenever they do not have a power-up. The player is unaffected by attacks from airborne units while they are playing on the ground level, but the ship is automatically brought back into the air after a certain period of time. The player can still be hit by attacks from ground units while they are on the ground level, and can also lose their ship by crashing into obstacles. The 8-way joystick controls the player's movements, and one button is used for shooting, and the other is used for descending to the ground (or un-equipping wings). The background image continues infinitely when the player scrolls in the horizontal directions.
Completing the final level of the game causes the score counter to increase to 9,999,999 points, which the player can enter as their high score. The player can also score cheap points by equipping and un-equipping their power-up. Pressing the button twice while the un-equipping animation is occurring cause the player to gain 2,000 points. The player gains an extra life every 40,000 points, so it is possible to gain lives almost infinitely. If the player gains over 10,000,000 points in this way before completing the final level, the counter takes over 20 minutes to increase to 99,999,999 points.
Family Computer versionEdit
The game was ported to the Family Computer in 1986, but many changes were made to power-ups, enemy attack patterns, and enemy appearances, making the gameplay considerably different from the arcade version. New catchy background music was also added, and it also became possible to rapid-fire shots. Several warps and hidden items were also added, along with an ending screen.
8 different types of power-ups (wings) are included in the arcade version, each of which have characteristic strengths and weaknesses. Shooting down two cargo ships allows the player to equip a wing.
- Anti-Wing (A-WING): Allows the player to shoot in the backwards direction.
- Cannon-Wing (C-WING): Allows the player to shoot more powerful shots in the forward direction.
- Ground-Wing (G-WING): Allows the player to attack enemies on the ground.
- Jump-Wing (J-WING): Allows the player to attack with shots that travel high up and return to their original height to explode.
- Multiple-Wing (M-WING): Equips a rotating cannon on the ship, which allows the player to attack in multiple directions.
- Side-wing (S-WING): Allows the player to shoot in the horizontal directions.
- Van-Wing (V-WING): This allows the player to shoot a beam that spreads outwards from the player's ship. The beam's range is smaller than the W-WING power-up, and disappears once it hits any enemy unit or obstacle, or travels a certain distance. The power-up's actual name is the Barrier-wing (B-WING), but it was purposely misspelled to avoid overlapping with the game's title. The power-up's name is Van-wing in the Family Computer version.
- Wide-Wing (W-WING): This power-up is similar to the V-WING, and allows the player to shoot a beam in the forwards direction. Hitting any part of an obstacle with this beam causes the entire structure to disintegrate as well.
Ever 4 levels, the player can choose which power-up they want to appear next. Suitable power-ups appear for each level, but it is possible to complete each level without equipping the power-up. However, the final boss cannot be defeated without certain power-ups (J-WING, S-WING, or V-WING), and the player is returned to a point where they can obtain these power-ups once their ship is destroyed.
Family Computer power-upsEdit
There are no enemies on the ground in the Family Computer version, so the G-WING power-up is not included. 3 new power-ups were added in place, bringing the total number of power-ups up to 10. There are also 3 more hidden power-ups that allow the player to destroy obstacles in certain levels.
- Dyna-Wing (D-WING): Allows the player to shoot a wave-like beam into the forward direction. Its range is limited, and takes time to reload, but is extremely effective against organic enemies.
- Fire-Wing (F-WING): Allows the player to shoot fire in the forwards direction. It is also very limited in terms of range, but is extremely powerful, and can even clean up bosses in a short period of time.
- Hammer-Wing (H-WING): Two large iron spheres revolve around the player's ship, shielding it from enemy units and attacks. It also allows the player to shoot with infinite range in the forwards direction.