Perspective: Side view
Visual: 2D scrolling
Gameplay: Arcade, Shooter
Setting: Sci-fi / futuristic
Published by: Konami Co.
Developed by: KCE Tokyo
Platform: PlayStation (PSX, PS1)
The basic gameplay of Gradius Gaiden stays true to the series. However, two ships are added, whose armament configuration is new. In addition, there are various changes to the weapon mode. Many weapons and builds from Gradius III have disappeared, although in exchange you can choose between 4 different ships, with a unique weapon configuration. It also adds a function already seen in the Gradius of the MSX, and, above all, in Salamander 2; the possibility of increasing the power of missiles and lasers. Another addition to mention is a new shield, called 'Limit', which provides invulnerability for 3 seconds.
The difficulty level can be adjusted from very easy to very difficult, going through a total of 7 difficulty modes. In the easiest, the most complex boss attacks are eliminated and the number of ships on the screen is drastically reduced.
Finally, you can choose the order of appearance of each element in the weapon bar, placing, for example, the shield at the beginning and the double shot at the end. This option has only been seen in this game, and it can be very useful.
- Vic Viper: Classic configuration of the Gradius series. Dual-level missiles are capable of hitting multiple targets with just one, and the dual-level laser allows larger shots to be fired.
- Lord British: Classic configuration of the Salamander saga, with missiles that fall in both directions, ring-shaped lasers and more.
- Jade Knight: All weapons on this ship are green, including their options. Their missile is the Gradius II Expansive Bomb. It also has two types of lasers: round and pulse. The surrounding laser is the most notable weapon in the game, firing laser rings from the ship. The pulsing lasers are two short parallel lasers that go in a straight line.
- Falchion β: The weapons of this ship are a mixture of different configurations of the saga. The Falchion has two-way missiles, which fall to the ground, break in two, and go left and right. It also has a double shot capable of firing in three directions (0, 45 or 90 degrees), depending on the direction of the enemies. The laser is taken from the Parodius saga, in a shot used by Pentarou from Parodius Da! until later titles in the saga.
- Stage 1: Beyond the White Storm. An icy level, full of dangerous snow avalanches, ice ramps and all kinds of enemies. The boss is Blizzard Crawler, a snow worm that will attack by throwing snowballs and try to eat you.
- Stage 2: Requiem for Revengers. This level is the tomb of old enemy ships of the saga, where you can find Big Core, Tetran or Crystal Core, among others. The level is divided in two towards the end, giving a choice between two bosses. The top one, Nobil, is a four-legged arachnid robot that will use powerful lasers and its jumps to try to knock you down. The one below, Grave, is a small robot that will collect pieces of ships, attacking with them and its long arms.
- Stage 3: Into the Crystal Cage. An area full of crystals that reflect or redirect your laser, creating the most varied effects. You must destroy those crystals that block your path, and use these to attack the various enemies that will cross the area. The boss is Shining Core, a new version of the typical enemy ship, which will launch various lasers at you.
- Stage 4: Ruins of Silence. The moai level that you cannot miss. On this occasion, there are not only moai that turn around, but also some dangerous ones, such as those capable of launching a laser with their eyes. The boss is Moai Dimension, a pair of moais that will launch drone shots and hoops that will dwarf when shot.
- Stage 5: Organic Fortress. Organic base similar to that seen in previous Gradius and Salamander. Organic balls will cling to the walls, blocking the way. The boss is Mad Skin, a sphere embedded in the skin, which will launch dangerous attacks that can destroy you in one hit.
- Stage 6: Green Inferno. A jungle area, full of plants and flowers. Dangerous claws will try to destroy you. The boss is Stinger Kid, a plant that will throw seeds at you. After rotting, it will turn into Hunter Fang, a dangerous skeletal plant that will try to kill you with bites and other attacks. After falling, he will resurrect as Gigas Rose, a dangerous flower that will fire multiple shots.
- Stage 7: On the Event Horizon. The classic mountainous area of the saga. However, this time it has the addition of a black hole, which will engulf the stage and those ships that risk getting closer. The boss is Kraken, a new version of the classic ship, which will use long arms and various shots to finish you off.
- Stage 8: Formidable Guardians. The level of boss rain. Laser Tetran will appear first, a ship that will fire four lasers, clearly limiting the flight space. Then Death Double will come out, a ship that will use two Death Mk-IIs, attacking all three together. Later the Triple Core will emerge, three spheres that will orbit collaborating in various attacks. Deltatry will arrive, a ship that will launch a brutal amount of shots, in addition to other attacks that are difficult to dodge. Jagler Core will emerge, a ship that will launch multiple lasers, not counting other very dangerous attacks. The final boss is Neo-Bigcore, a ship that will fire blast shots, huge lasers that will fill much of the screen and other attacks like that. If you are in the second round or later, Heaven's Gate will also appear, a ship that will launch a brutal amount of lasers against you, being a feat to avoid them all.
- Stage 9: Fate .... Last level of the game, again on a mechanical basis, with pieces that move, parts of the stage that try to crush you and all the classic traps of the last level of each game in the saga. Along the way you will meet some bosses, such as Boost Core, a ship that you will have to chase at high speeds, while avoiding all kinds of objects. Gunner Wall, a classic armored door from the series, will also cut you off. Heavy Ducker, a two-legged machine with various ammunition, will also try to destroy you. SOL will be the last thing that tries to tear you apart before reaching the final boss, being a many-legged mechanical wheel. Finally, you will have to defeat O.V.U.M., the final boss of the Salamander, who this time will be able to transform into various enemies of the game, until he ends up perishing.