ダウンフォール（Downfall）

In the midst of those terrible nightmares that keep you up at night, you leap into the abyss to restore the life destroyed by your dealings with the devil.

Faust, the protagonist, had a successful life due to his dealings with the devil, but now he suffers from terrible dreams each night. To find what lies at the end of those dreams—to end it all—he decides to plunge into those nightmares and face the monsters that lie within...

Downfall is a roguelike hack-and-slash game where you develop your character by stylishly defeating the endless waves of enemies within your nightmare.