Adiya Var, Kanakai Queen

Whenever Adiya Var, Kanakai Queen attacks, tap target creature you don't control, that creature does not untap on the next untap step.
Other Merfolk you control get +1/+1.
As long as you control a Plains, Humans you control get +1/+1.
{g}{w}{u}: Return target creature you control to its owner's hand.