Thopter Battlesphere

When Thopter Battlesphere enters the battlefield, create three 1/1 colorless Thopter artifact creature tokens with flying.
Whenever Thopter Battlesphere attacks, you may tap X untapped Thopter you control. If you do, Thopter Battlesphere gets +X/+0 until end of turn and deals X damage to the player or planeswalker it's attacking.