Baldr Sky (バルドスカイ, Barudosukai) is a duology of Japanese adult visual novels with 2D action elements developed by Giga.

[1] The first game, named Baldr Sky Dive1 "Lost Memory” was released in Japan on March 27, 2009, for Windows.

A fandisc called Baldr Sky DiveX "Dream World" was released in Japan on September 24, 2010.

[4] A majority of Baldr Sky's gameplay consists of reading the text that's rendered on screen and supported with audio for voices.

The player will occasionally be presented with choices to select which may or may not determine the outcome of the game.

The player is given a chance to upgrade or modify the equipment of the mecha prior to a series of battles.

Baldr Sky takes place in Japan some time in the future during the 21st century.

The abilities of these nanomachines range from medical purposes for curing ailments and modifying the taste of food.

People engage in combat online in simulacrums, the name of the mecha units in the game, or with viruses (unmanned robots).

Kou wishes to uncover the truth about what happened that day and to prevent another tragedy from occurring again, as his girlfriend Sora was killed by the nanomachines.

Kou has been chasing after the truth behind the incident known as "Gray Christmas", in which he lost the person most precious to him.

She disappeared after Gray Christmas, but later reappeared before then undergoing memory restoration process Kou, dressed in an army uniform and heavily cyborgized.

Sora's little sister, she met Kou who saved her from bullying by her peers due to her illness.

Moved with Kou in Kisaragi dormitory when they lost their previous place due to a certain incident with their upperclassmen.

A woman with a childlike appearance, and a capable underground doctor, who lives in the Suzushiro City's slums.

On September 24, 2010, GIGA also published a fandisc called "BALDR Sky DiveX: Dream World", which included many scenes that weren't mentioned in Dive1 and Dive2, such as the memories of Kou while he was a mercenary with Rain.