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 - $0.70
Lightly Played - $0.60
Moderately Played - $0.50
Heavily Played - $0.30
Damaged - $0.20
Near Mint French - $0.70
Lightly Played French - $0.60
Moderately Played French - $0.50
Heavily Played French - $0.30
Damaged French - $0.20