Nature's Voice

Whenever a creature attacks you or a planeswalker you control, you may pay {1}{g} and tap Nature's Voice. If you do, return target attacking creature to it's owner's hand.
{1}{g}{t}: Put 2 Calm counters on target creature.
Any creature with a Calm counter on it cannot attack, block, crew vehicles, or activate abilities, and does not untap during it's controller's upkeep. During each player's upkeep, that player may remove 1 Calm counter from each creature they control.