Killy, Eternal Seeker

When Killy, Eternal Seeker enters, create the Graviton Beam Emitter, a legendary colorless Indestructible Equipment artifact token with "Equipped creature gets +10/+0 and trample" and Equip {5}.

When Killy, Eternal Seeker would leave the battlefield, you may put it into its owner's library third from the top instead.

{t}{w/b}{w/b} : Equip the Graviton Beam Emitter to Killy, Eternal Seeker.