Gradius Gaiden

Gradius Gaiden is a horizontally scrolling shooter game where the player controls one of four different starships — the Vic Viper, Lord British, Jade Knight and Falchion β — in their mission to eradicate the Bacterian army before they destroy the planet Gradius. Gameplay itself remains relatively the same compared to previous installments; the player must complete each of the game's stages while shooting down enemies and avoiding collision with either them, their projectiles, or the terrain. Some enemies drop glowing Power Capsules when destroyed, which when collected will highlight a weapon on the player's "Power Meter", located at the bottom corner of the screen. Collecting additional Power Capsules will give the player access to better, stronger weapons. These weapons include missiles, a double shot, lasers, and glowing orbs known as "Options" that follow the player and will fight alongside them.

Gradius Gaiden features many new additions to the core gameplay. It was the first game in the series to include two-player simultaneous play. Each of the player's four ships feature their own unique set of weapons; the Vic Viper features the standard Gradius arsenal of weapons; the Lord British features the Ripple Laser from Salamander and a pulsating shot named the "Disruptor"; the Jade Knight has a "Circle Laser" that creates deadly rings surrounding it; the Falchion β has a powerful "Black Hole Bomb" projectile that will suck in any enemies it comes into contact with. At the start of the game, the player can modify the placement of items in their Power Meter to their liking; for instance, the Options can be moved to the very front of their meter, requiring only one Power Capsule. Two new shields were added; the Guard, which makes the player invulnerable to terrain, and the Limit, which gives the player full invincibility for three seconds.

Gradius Gaiden was directed by Seki Teisaku. He was assisted in production by designers Kobayashi Takayki and Chigasaki Kei, sound designer Miura Norikazu, and programmers Yamazaki Yukihiro and Isobe Neiichi, among others. Most of the staff behind the project previously worked on Gradius Deluxe Pack (1996), a compilation of Gradius and Gradius II the Sega Saturn and PlayStation. This familiarized them with the core mechanics of the Gradius series.

Teisaku's goal was to refine and build upon many of the franchise's pre-existing concepts and ideas, while simultaneously providing an exciting and new experience for shooter fans. For this reason, team chose to name it Gaiden, the Japanese term for "side-story". This also allowed them to experiment with different ideas; while the name Gradius IV was considered, it was dropped to prevent them from sticking only to mechanics established in earlier installments.

Gradius Gaiden was well received by critics, and is seen as one of the best games in the Gradius franchise. It sold a total of 34,383 copies in its lifetime.

Several expressed admiration towards its visuals and graphical style. GameSpot's Chris Johnston felt that, while not as impressive as those in RayStorm or Star Fox 64, were excellent, especially its detailed backgrounds. Lord Mathias of Super GamePower found them to be well-designed and vibrant, and posing some impressive transparency and rotation effects; a writer for Ação Games agreed. The four reviewers from Famitsu stated it was one of the best-looking shooters on the PlayStation, as did Super Juegos.