Synopsis
Valkyrie, Kazuto, Akina, Hydra, and their companions return for further adventures when the Key of time makes an unexpected appearance alongside various other enigmatic events. Everything appears connected to an individual called "Valkyrie Ghost," who has the sole objective of taking Kazuto for herself. Uniting against this apparently invincible enemy, they investigate the hidden history of Valkyrie's native world, Valhalla.