When Myr Battlesphere enters the battlefield, create four 1/1 colorless Myr artifact creature tokens. Whenever Myr Battlesphere attacks, you may tap X untapped Myr you control. If you do, Myr Battlesphere gets +X/+0 until end of turn and deals X damage to the player or planeswalker it's attacking.
Near Mint - $400
Lightly Played - $300
Moderately Played - $300
Heavily Played - $200
Damaged - $200
Near Mint Spanish - $400
Lightly Played Spanish - $300
Moderately Played Spanish - $300
Heavily Played Spanish - $200
Damaged Spanish - $200