When Oath of Teferi enters the battlefield, exile another target permanent you control. Return it to the battlefield under its owner's control at the beginning of the next end step.
You may activate the loyalty abilities of planeswalkers you control twice each turn rather than only once.
The exiled card will return to the battlefield at the beginning of the next end step even if Oath of Teferi is no longer on the battlefield at that time.
If you somehow control more than one Oath of Teferi, you wonâ€™t be able to activate abilities of planeswalkers you control more than twice in one turn.
If the exiled card is an Aura, that cardâ€™s owner chooses what it will enchant as it returns to the battlefield. An Aura put onto the battlefield this way doesnâ€™t target anything (so it could be attached to an opponentâ€™s permanent with hexproof, for example), but the Auraâ€™s enchant ability restricts what it can be attached to. If the Aura canâ€™t legally be attached to anything, it remains exiled.
If a token is exiled this way, it ceases to exist and wonâ€™t return to the battlefield.
For Oath of Teferiâ€™s second ability, you may activate the same ability of a planeswalker twice, or you may activate two different abilities of that planeswalker.