Adreus, Keeper of Armageddon is a Fiend XYZ Monster with Attribute DARK, Level 5, ATK 2600, DEF 1700.
Xyz Monsters are usually Summoned using materials of matching Level; their effects often detach materials as cost.
On the current TCG and OCG Forbidden & Limited lists tracked here, Adreus, Keeper of Armageddon is Unlimited.
YGOPRODeck lists Adreus, Keeper of Armageddon for these formats: Duel Links, TCG, OCG, Master Duel.
A listed print of Adreus, Keeper of Armageddon appears in Battle Pack: Epic Dawn (BP01-EN030) at Rare rarity.
Among markets shown on this page, the lowest listed snapshot for Adreus, Keeper of Armageddon is about $0.24 on TCGPlayer (prices change frequently).
