Excalibur, Sword of Eden 72 (Universes Beyond: Assassin's Creed)

This spell costs {X} less to cast, where X is the total mana value of historic permanents you control. (Artifacts, legendaries, and Sagas are historic.) Equipped creature gets +10/+0 and has vigilance. Equip legendary creature {2}

NM - $28.00
LP - $22.50
MP - $17.00
HP - $11.50
DMG - $6.00