Anuro, Anurid Manipulator

Whenever another frog enters the battlefield
under your control, put a +1/+1 counter on that
creature. Then you may pay {1}, if you do, target
creature an opponent controls becomes a 1/1
blue frog and loses all abilities until end of turn.
{u}{g/u}{g/u} {t}: Each opponent chooses a frog they control, you gain control of those frogs.
(Activate once per turn and during your turn.)