Possibly incorrect behavior on ******* taker
I was playing in a historic brawl match and the following happened.
My opponent had a mind stone in play.
I played ******* taker targeting his mind stone.
The mind stone correctly was exiled and I was given the opportunity to cast it.
I did not have sufficient mana to cast it, so I passed the turn.
My opponent untapped and and played Mirrorhall Mimic choosing to copy my ******* taker and targeted my ******* Taker with the ETB effect.
My ******* taker was correctly exiled and my opponent's mind stone was correctly removed from exile and put back on the battlefield under their control.
My opponent had no mana left and passed the turn.
On my turn I played Ugin, the Ineffable, and used it's -3 ability to destroy my opponent's ******* Taker(Mirrorhall Mimic).
My ******* taker then returned to the battlefield under my opponent's control, my opponent was able to choose its ETB target, and the mirrorhall mimic entered my oppponent's graveyard.
As far as I know the ******* taker should have entered my side of the battlefield as I was the owner of the card and the controller before it was exiled.
Please correct me if I'm wrong.
I am playing on PC.