The Gradius (グラディウス, Guradiusu, pronounced: Gra-dee-us) games, first introduced in 1985, make up a series of scrolling shooter video games published by Konami for a variety of portable, console and arcade platforms. In many games in the series, the player controls a ship known as the Vic Viper. In other games of the series, ships the player controls include the Lord British Space Destroyer, Metalion, Sabel Tiger, Thrasher, Vixen, Alpinia, Super Cobra, Jade Knight, and the Falchion β.

Salamanders are a group of amphibians typically characterized by a lizard-like appearance, with slender bodies, blunt snouts, short limbs projecting at right angles to the body, and the presence of a tail in both larvae and adults. All present-day salamander families are grouped together under the scientific name Urodela. Salamander diversity is most abundant in the Northern Hemisphere and most species are found in the Holarctic ecozone, with some species present in the Neotropical zone.

Salamanders never have more than four toes on their front legs and five on their rear legs, but some species have fewer digits and others lack hind limbs. Their permeable skin usually makes them reliant on habitats in or near water or other cool, damp places. Some salamander species are fully aquatic throughout their lives, some take to the water intermittently, and others are entirely terrestrial as adults. Unique among vertebrates, they are capable of regenerating lost limbs, as well as other damaged parts of their bodies. Members of the family Salamandridae are mostly known as newts and lack the costal grooves along the sides of their bodies typical of other groups. The skin of some species contains the powerful poison tetrodotoxin and these salamanders tend to be slow-moving and have bright warning coloration to advertise their toxicity. Salamanders typically lay eggs in water and have aquatic larvae, but great variation occurs in their lifecycles. In some species and some harsh environments, salamanders reproduce while still in the larval state.

In literature and legend, the salamander is associated with fire, being supposedly unharmed by the flames, while clothes made from its skins or 'wool' were believed to be incombustible. More plausibly, salamanders were said to be intensely poisonous. Despite this, salamander brandy, a drink prepared by dunking live salamanders in fermenting fruit juices, is reputed to have hallucinogenic and aphrodisiac properties. The salamander's ability to regenerate lost body parts is being investigated and research is ongoing into any applications this may have for human medicine.

The Maze of Galious (魔城伝説II ガリウスの迷宮 Majō Densetsu Tsū: Gariusu no Meikyū?), is the sequel to Konami's MSX game Knightmare. While the first game was an overhead, vertical scrolling shooter, The Maze of Galious is a side-view, flick-screen platform game. The player controls Popolon and Aphrodite, entering the evil priest Galious' castle to free their yet-to-be-born son Pampas from the priest's evil clutches. Being able to control Popolon and Aphrodite means the player can switch between two characters that have slightly different abilities. For example, Popolon can push stones and open heavy doors. On the other hand, Aphrodite survives longer under water and she can shoot more projectiles. Should either character die, the other can visit a shrine and pay for resurrection. Unlike typical platform games, both characters can survive some damage as they have hit point bars.
The game has several types of enemies, each with strengths and weaknesses. Some monsters are immune to frontal attacks, some are more vulnerable to fire and so on. Ten different bosses are to be fought too. Defeating a boss will give the player a key that is used to unlock doors to other boss areas. In-game saving is provided by giving player an encoded password.