Valkyrie no Densetsu is a 1989 action-adventure video game developed and published by Namco for arcades. It is a follow-up to the Family Computer game Valkyrie no Bōken (1986). Players control the warrior maiden Valkyrie and her lizard-like companion Kurino Xandra as they set out to drop a mythical item called the Golden Seed into the Northern Fountain to replenish the dying crop fields of Xandra Land. Gameplay involves defeating enemies and collecting gold to purchase magical spells and weapons in shops.

Valkyrie no Densetsu was the creation of Namco artist Hiroshi Fujii and a designer only known by the pseudonym of "Koakuman". The game's world, the fictional kingdom of Marvel Land, was greatly inspired by Viking tales from northern Europe and the Middle Ages, with a heavy emphasis on having a sort-of "magical" feel of it. It was originally meant to be a four-player action game in the vein of titles like Gauntlet with a cabinet-linking system similar to Final Lap, which was scrapped later on. Characters were made to have personality and depth, a design choice inspired by The Wizard of Oz.

Valkyrie no Densetsu was released in arcades to critical acclaim for its gameplay, characters, and world. Namco ported the game to the PC Engine in 1990, a conversion that was met with a more mixed response for its difficulty, downgraded graphics, and altered gameplay. The game was mostly unknown outside Japan until the release of Namco Museum Vol. 5 in 1997, which renamed the game to The Legend of Valkyrie and was fully translated into English. Several additional ports were made, including those for Windows, Japanese mobile phones, and the Wii's Virtual Console.

Valkyrie no Densetsu is a top-down action-adventure game. The player takes control of the sword-armed warrior maiden Valkyrie, while a second player can join in as Valkyrie's lizard-like companion Kurino Xandra. Both characters have a projectile weapon that can be shot at enemies to defeat them, as well as health meters that deplete if they are hit by an enemy or projectile. A fraction of their health will also be removed if either fall into a pit or off a cliff. A time limit is present, indicated by an hourglass towards the bottom of the screen, which will deplete as the stage progresses – allowing this timer to fully empty will result in the game being over.

Both players can collect gold coins by defeating enemies, which can be used in stores found throughout the game to purchase magic spells, weapons and other items. Some enemies can drop bubble-like items that can be exchanged with certain NPCs in return for powerful magic spells that can deal great damage against enemies. Item prices in shops increase as the game progresses. Players can find treasure chests in certain places that yield powerful, sometimes rare items that are useful for later sections of the game. The game spans a total of eight areas, featuring locations such as grassy plateaus, icefields, caves and dungeons. Each area concludes with a boss that must be defeated to progress. The final area features a showdown the game's antagonist Kamooz.

Small parts of the story to Valkyrie no Densetsu are told through in-game cutscenes and dialogue, while much of it is instead found in various pieces of Namco promotional material. Continuing after the events of the first game, following the restoration of peace to the kingdom of Marvel Land the inhabitants of Xandra Land notice their kingdom becoming barren of resources, with the cropfields providing the Xandra Land people's food drying up. In an effort to save his family and home, Kurino Xandra embarks on a quest to retrieve a mystical item called the Golden Seed, said to grant the wishes of whoever drops it into the Northern Spring. After beginning his search for the Golden Seed, Xandra is joined by Sabina, a member of the Koakuman tribe, and Zuul, a former bandit who has a map potentially leading to the seed. Following the map leads the trio to an odd formation of rocks with a golden trident atop them, which becomes Xandra's primary weapon.

One evening, the three encounter an old woman in the forest, advising them to visit an abandoned village that had been destroyed many years ago. As they investigate, Xandra and company are met by the warlord Kamooz and his group of soldiers. Kamooz, responsible for spreading destruction and chaos across Marvel Land, is also looking for the Golden Seed to enslave the inhabitants of the kingdom and make them his personal slaves, attacking Xandra and his friends. Just as the situation begins to escalate, a mythical warrior named Valkyrie descends from the heavens and chases away Kamooz and his soldiers. Valkyrie agrees to join Xandra, Sabina and Zuul to put an end to Kamooz and retrieve the Golden Seed. After making their way to the Northern Spring, Valkyrie and Xandra encounter Kamooz once more and manage to defeat him before he drops the Golden Seed into the spring; with her mission fulfilled, Valkyrie bids farewell to Xandra and his friends as she leaps back into the heavens.

Valkyrie no Densetsu was the creation of Namco character artist Hiroshi Fujii, who previously worked on the game's predecessor Valkyrie no Bōken: Toki no Kagi Densetsu, and a designer only known by the pseudonym of "Koakuman". Prior to designing Densetsu, Fujii had previously worked for Namco's design department, a division of the company that produced toys, electro-mechanical arcade games, and robotics. When the department was eventually dissolved, Fujii was swiftly brought aboard Namco's core video game design division due to his prior experience with console games, and became the head designer for the new game. During the project's planning stage, Fujii used many of his sketches and artwork he created for Valkyrie no Boken to rework into Densetsu, including several enemies and locations. The game's fictional world was inspired by the Middle Ages and ancient Europe, featuring a sense of "magic" in-between. The team envisioned the player exploring a vast, open-world, with transitioning seasons and landscapes, but the vertical orientation of the arcade monitor left much of this idea heavily altered or cut out entirely.