Kayla's Music Box

{W}, {T}: Look at the top card of your library, then exile it face down. (You may look at it any time.)
{T}: Until end of turn, you may play cards you own exiled with Kayla's Music Box.

Expert-Level Safe

When Expert-Level Safe enters, exile the top two cards of your library face down.
{1}, {T}: You and target opponent each secretly choose 1, 2, or 3. Then those choices are revealed. If they match, sacrifice Expert-Level Safe and put all cards exiled with it into their owners' hands. Otherwise, exile the top card of your library face down.

Ugin, the Ineffable

Colorless spells you cast cost {2} less to cast.
+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.
−3: Destroy target permanent that's one or more colors.

Bomat Courier

Haste
Whenever Bomat Courier attacks, exile the top card of your library face down. (You can't look at it.)
{R}, Discard your hand, Sacrifice Bomat Courier: Put all cards exiled with Bomat Courier into their owners' hands.

Jester's Scepter

When Jester's Scepter enters, exile the top five cards of target player's library face down. You may look at those cards for as long as they remain exiled.
{2}, {T}, Put a card exiled with Jester's Scepter into its owner's graveyard: Counter target spell if it has the same name as that card.

Gustha's Scepter

{T}: Exile a card from your hand face down. You may look at it for as long as it remains exiled.
{T}: Return a card you own exiled with Gustha's Scepter to your hand.
When you lose control of Gustha's Scepter, put all cards exiled with Gustha's Scepter into their owner's graveyard.

Headliner Scarlett

Haste
When Headliner Scarlett enters, creatures target player controls can't block this turn.
At the beginning of your upkeep, exile the top card of your library face down. You may look at and play that card this turn.

Wall of Mourning

Defender
When Wall of Mourning enters, exile a card from the top of your library face down for each opponent you have.
Coven — At the beginning of your end step, if you control three or more creatures with different powers, put a card exiled with Wall of Mourning into its owner's hand.

Pyxis of Pandemonium

{T}: Each player exiles the top card of their library face down.
{7}, {T}, Sacrifice Pyxis of Pandemonium: Each player turns face up all cards they own exiled with Pyxis of Pandemonium, then puts all permanent cards among them onto the battlefield.

Death in Heaven

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Target player mills two cards, then exiles their graveyard.
III — Put all creature cards exiled with Death in Heaven onto the battlefield face down under your control. They're 2/2 Cyberman artifact creatures.

Ignorant Bliss

Exile all cards from your hand face down. At the beginning of the next end step, return those cards to your hand, then draw a card.