The owner is the player who brought the card into the game, the (default) controller of a permanent is the player under whose control it entered the battlefield. Zedruu gives away control of a permanent you control, so now that other player is the controller. You can't give away control of something you no longer control with Zedruu.
The Jinxed Idol is still a card you own (Zedruu would be a bit useless otherwise, wouldn't she?), but since you no longer control it you cannot target it with Zedruu's activated ability.
Let´s say that i have Zedruu the Greathearted out on the battlefield and I cast Jinxed Idol and then spend 3 mana from Zedruu the Greathearted to let one of my opponents gain control of it. Since I gave up the control of Jinxed Idol is it still my card? Could I for instance useZedruu the Greathearted again to give Jinxed Idol to another opponent if i want?
Former Rules Advisor
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