It was powered by Unreal Engine 3 , featuring high-end 3D graphics for its time.

The game featured an "all-star" lineup of Japanese game composers, including: Yoko Shimomura ( Kingdom Hearts ) Keiichi Okabe ( NieR ) Kenji Ito ( SaGa series) Hiroki Kikuta ( Secret of Mana ) Gameplay Mechanics

The gameplay was often compared to iNiS's previous hit, Elite Beat Agents .

Because the game was officially discontinued and removed from app stores in 2014, "Demons' Score 7z" typically refers to found on third-party sites. The .7z format is a high-compression archive used to store these large game assets, often used by the emulation and preservation communities to keep delisted mobile titles playable.

Each stage typically consisted of a "Track 1" (clearing lesser demons) and a "Track 2" (a cinematic boss battle against a "Great Demon of the Abyss").