Vivien, Champion of the Wilds says:
"{-2}: Look at the top three cards of your library. Exile one face down and put the rest on the bottom of your library in any order. For as long as it remains exiled, you may look at that card and you may cast it if it's a creature card."

Thief of Sanity says:
"Whenever Thief of Sanity deals combat damage to a player, look at the top three cards of that player's library, exile one of them face down, then put the rest into their graveyard. You may look at and cast that card for as long as it remains exiled, and you may spend mana as though it were mana of any type to cast that spell."

Ugin, the Ineffable says:
"{+1}: Exile the top card of your library face down and look at it. Create a 2/2 colorless Spirit creature token. When that token leaves the battlefield, put the exiled card into your hand."

By reading this abilities I understand that you can see the card exiled by Ugin when you exiled it but you can't do it afterward. But the Oracle and released notes says otherwise and I don't understands why.

Oracle :

Once you look at the exiled face-down card once, you may look at it again any time you wish.

In addition there is Induced Amnesia who says:
"When Induced Amnesia enters the battlefield, target player exiles all cards from their hand face down, then draws that many cards."
And the Oracle claim that player can't look at exiled card.

Can someone explain me what I'm missing ?


EDIT: CR 406.3 is what I was missing. It's seems not clear for me so it will be the same for players.

Edited Camille POTTIER (May 17, 2019 10:08:32 PM)

Hi,

As you noticed, 406.3 is the rule that matters here - it lets you look at a face down card in exile as long as you were allowed to look at it before (that's why Ugin tells you to exile the card face down, *then* look at it - to give you permission to look at it in the future as long as it remains exiled).

406.3. Exiled cards are, by default, kept face up and may be examined by any player at any time. Cards “exiled face down” can’t be examined by any player except when instructions allow it. However, once a player is allowed to look at a card exiled face down, that player may continue to look at that card as long as it remains exiled, even if the instruction allowing the player to do so no longer applies. A card exiled face down has no characteristics, but the spell or ability that exiled it may allow it to be played from exile. Unless that card is being cast face down (see rule 707.4), the card is turned face up just before the player announces that they are playing the card (see rule 601.2).[/quote[

Also keep in mind that we have the following Gatherer ruling for players who are curious and don't know the Comp Rules:

Once you look at the exiled face-down card once, you may look at it again any time you wish.

Thanks,
Nathan Long
Magic Rules NetRep