Library of Leng

You have no maximum hand size.
If an effect causes you to discard a card, discard it, but you may put it on top of your library instead of into your graveyard.

Dream Cache

Draw three cards, then put two cards from your hand both on top of your library or both on the bottom of your library.

Penance

Put a card from your hand on top of your library: The next time a black or red source of your choice would deal damage this turn, prevent that damage.

Volrath's Dungeon

Pay 5 life: Destroy this enchantment. Any player may activate this ability but only during their turn.
Discard a card: Target player puts a card from their hand on top of their library. Activate only as a sorcery.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Hidden Retreat

Put a card from your hand on top of your library: Prevent all damage that would be dealt by target instant or sorcery spell this turn.

Combustible Gearhulk

First strike
When this creature enters, target opponent may have you draw three cards. If the player doesn't, you mill three cards, then this creature deals damage to that player equal to the total mana value of those cards.

Djinn of Wishes

Flying
This creature enters with three wish counters on it.
{2}{U}{U}, Remove a wish counter from this creature: Reveal the top card of your library. You may play that card without paying its mana cost. If you don't, exile it.

Zevlor, Elturel Exile

Haste
{2}, {T}: When you next cast an instant or sorcery spell that targets only a single opponent or a single permanent an opponent controls this turn, for each other opponent, choose that player or a permanent they control, copy that spell, and the copy targets the chosen player or permanent.

Brainstone

{2}, {T}, Sacrifice this artifact: Draw three cards, then put two cards from your hand on top of your library in any order.

Riverwise Augur

When this creature enters, draw three cards, then put two cards from your hand on top of your library in any order.

Zur's Weirding

Players play with their hands revealed.
If a player would draw a card, they reveal it instead. Then any other player may pay 2 life. If a player does, put that card into its owner's graveyard. Otherwise, that player draws a card.

Enter the Infinite

Draw cards equal to the number of cards in your library, then put a card from your hand on top of your library. You have no maximum hand size until your next turn.

Widespread Panic

Whenever a spell or ability causes its controller to shuffle their library, that player puts a card from their hand on top of their library.

Hidetsugu and Kairi

Flying
When Hidetsugu and Kairi enters, draw three cards, then put two cards from your hand on top of your library in any order.
When Hidetsugu and Kairi dies, exile the top card of your library. Target opponent loses life equal to its mana value. If it's an instant or sorcery card, you may cast it without paying its mana cost.

Survivor of the Unseen

Cumulative upkeep {2} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
{T}: Draw two cards, then put a card from your hand on top of your library.

The Raven's Warning

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Create a 1/1 blue Bird creature token with flying. You gain 2 life.
II — Whenever one or more creatures you control with flying deal combat damage to a player this turn, look at that player's hand and draw a card.
III — You may put a card you own from outside the game on top of your library.

Jeleva, Nephalia's Scourge

Flying
When Jeleva enters, each player exiles the top X cards of their library, where X is the amount of mana spent to cast Jeleva.
Whenever Jeleva attacks, you may cast an instant or sorcery spell from among cards exiled with Jeleva without paying its mana cost.

Doomsday

Search your library and graveyard for five cards and exile the rest. Put the chosen cards on top of your library in any order. You lose half your life, rounded up.

Conch Horn

{1}, {T}, Sacrifice this artifact: Draw two cards, then put a card from your hand on top of your library.

Blast of Genius

Choose any target. Draw three cards, then discard a card. Blast of Genius deals damage equal to the discarded card's mana value to that permanent or player.

Calibrated Blast

Reveal cards from the top of your library until you reveal a nonland card. Put the revealed cards on the bottom of your library in a random order. When you reveal a nonland card this way, Calibrated Blast deals damage equal to that card's mana value to any target.
Flashback {3}{R}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Jace, the Mind Sculptor

+2: Look at the top card of target player's library. You may put that card on the bottom of that player's library.
0: Draw three cards, then put two cards from your hand on top of your library in any order.
−1: Return target creature to its owner's hand.
−12: Exile all cards from target player's library, then that player shuffles their hand into their library.

Broadside Bombardiers

Menace, haste
Boast — Sacrifice another creature or artifact: This creature deals damage equal to 2 plus the sacrificed permanent's mana value to any target. (Activate only if this creature attacked this turn and only once each turn.)

Palantír of Orthanc

At the beginning of your end step, put an influence counter on Palantír of Orthanc and scry 2. Then target opponent may have you draw a card. If that player doesn't, you mill X cards, where X is the number of influence counters on Palantír of Orthanc, and that player loses life equal to the total mana value of those cards.

Sadistic Augermage

When this creature dies, each player puts a card from their hand on top of their library.

Bosh, Iron Golem

Trample
{3}{R}, Sacrifice an artifact: Bosh deals damage equal to the sacrificed artifact's mana value to any target.

Scroll Rack

{1}, {T}: Exile any number of cards from your hand face down. Put that many cards from the top of your library into your hand. Then look at the exiled cards and put them on top of your library in any order.

Omniscience

You may cast spells from your hand without paying their mana costs.

Gandalf the Grey

Whenever you cast an instant or sorcery spell, choose one that hasn't been chosen —
• You may tap or untap target permanent.
• Gandalf deals 3 damage to each opponent.
• Copy target instant or sorcery spell you control. You may choose new targets for the copy.
• Put Gandalf on top of its owner's library.

Telling Time

Look at the top three cards of your library. Put one of those cards into your hand, one on top of your library, and one on the bottom of your library.