As long as equipped creature is tapped, tapped creatures you control get +2/+0.
As long as equipped creature is untapped, untapped creatures you control get +0/+2.
: You may tap or untap equipped creature.
Equip
Search target player's library for a card and exile it. Then that player shuffles.
Gravestorm (When you cast this spell, copy it for each permanent put into a graveyard this turn. You may choose new targets for the copies.)
When this creature enters, create four 1/1 colorless Myr artifact creature tokens.
Whenever this creature attacks, you may tap X untapped Myr you control. If you do, this creature gets +X/+0 until end of turn and deals X damage to the player or planeswalker it's attacking.
Equipped creature gets +2/+2, has intimidate, and is a black Zombie. (A creature with intimidate can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Whenever a nontoken creature is put into your graveyard from the battlefield, you may pay . If you do, return that card to the battlefield and attach this Equipment to it.
Equip
, Sacrifice an artifact: Add an amount of 
equal to the sacrificed artifact's mana value.
: You may tap or untap equipped creature.
Equip 
