Gleylancer (グレイランサー) is a scrolling shooter game developed by Masaya. It was released in 1992 for the Sega Mega Drive game console.

Originally, the game was published only in Japan and South Korea. Still, the weapon selection screen at the start of the game is written completely in English.

The game was eventually released outside of Japan with a Virtual Console release in Europe and North America in 2008. Previously, an unofficial fan-made translation patch was made available, allowing non-Japanese players to understand the story.

The gameplay in Gleylancer is similar to most shoot 'em up games on the Mega Drive.

During the game, the Gleylancer can toggle through four different speeds. This is always done in a 1-2-3-4-3-2-repeat order, although the starting point can be chosen in the game options. By shooting silver and blue pods, the player can pick up various weapons which take the form of Gunners:

• Twin Shot: Fires a rapid stream of double blue energy pulses. Basic weapon.
• Laser: Fires thin white lasers. Not quite as powerful as Twin Shot, but pierces enemies and inflicts multiple strikes on large enemies.
• 5-Way: Shoots an arc of five purple energy pulses. Although the range is excellent, it suffers from a low fire rate—only one salvo from each Gunner can be on-screen at once.
• Burner: Shoots moderate-range fireballs that can track along any solid surfaces they strike.
• Spread Bomb: Shoots flickering blue bombs. The bombs have low speed and fire rate, but create secondary explosions upon striking an enemy or solid surface.
• Saber: Generates a continuous, short/mid-range beam of purple energy.
• Bound Shot: Fires a stream of rapid green energy pulses that reflect off of solid surfaces.

The player can have up to two Gunners. Both Gunners will always have the same weapon, with subsequent power-ups overwriting them both.

In addition, at the beginning of the game, the player chooses one of seven formations to use for the Movers that the Gunners are mounted on.

• Normal: The Gunners will face in the same direction the ship is moving. While C is held down, the facing of the Gunners is locked, regardless of how the ship moves.
• Reverse: Like Normal, except that the Gunners will face the opposite direction of the ship's movement.
• Search: The Gunners will automatically aim at the nearest enemy. Tapping C will toggle between the Gunners aiming at same or different targets.
• Multi: Each Gunner is restricted to either the top or bottom 180 degree arc of the ship. Horizontal motion will cause the Gunners to swivel in that direction. Although this prevents concentrated fire in any direction except the horizontals, it permits three-way firing. Holding down C, or only moving vertically, will keep the Gunners aiming in the same directions.
• Multi-R: Like Multi, except the Gunners will swivel in the direction opposite the ship's horizontal motion.
• Shadow: The Gunners imitate every motion of the ship, following a short distance behind. However, they can only fire forward. Holding down C fixes their positions relative to the ship.
• Roll: The Gunners constantly spin around the ship at 180 degrees from each other. Normally, they shoot away from each other, resulting in a kind of spiral fire pattern. Tapping C toggles between this and the Gunners both firing forward.