Excalibur, Sword of Eden

Legendary Artifact — Equipment

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}

Forged to end the Isu’s war. Wielded by humans to wage it.