As an additional cost to cast this spell, sacrifice a blue permanent.

Counter target spell.

Raid -- If you attacked this turn, you may pay {U} rather than pay this spell's mana cost.

Counter target spell.

Target creature gets -1/-1 until end of turn.

Draw a card.

Draw a card for each Bird on the battlefield.

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Destroy target nonblack creature. It can't be regenerated.

Draw a card.

Counter target artifact or enchantment spell.

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.

You draw a card at the beginning of the next turn's upkeep.

Flying

When Augury Owl enters the battlefield, scry 3. (Look at the top three cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)

Flying

Foretell {1}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Flying

Sacrifice Aven Augur: Return up to two target creatures to their owners' hands. Activate only during your upkeep.

Flying

When Aven Fateshaper enters the battlefield, look at the top four cards of your library, then put them back in any order.

{4}{U}: Look at the top four cards of your library, then put them back in any order.

Flying (This creature can't be blocked except by creatures with flying or reach.)

When Aven Fisher dies, you may draw a card.

Whenever a creature dies, put a charge counter on Black Market.

At the beginning of your precombat main phase, add {B} for each charge counter on Black Market.

This spell costs {3} less to cast if a creature died this turn.

Flying, deathtouch

As Choked Estuary enters the battlefield, you may reveal an Island or Swamp card from your hand. If you don't, Choked Estuary enters the battlefield tapped.

{T}: Add {U} or {B}.

{T}: Add {U}.

{T}: Add {B}.

{T}: Add one mana of any color in your commander's color identity.

Counter target spell.

Enchant creature

Whenever enchanted creature deals damage to an opponent, you may draw a card.

Flying

You have no maximum hand size.

Whenever a creature token you control deals combat damage to a player, draw a card.

Darkslick Shores enters the battlefield tapped unless you control two or fewer other lands.

{T}: Add {U} or {B}.

Draw a card. Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Scry 2, then draw a card.

Search your library for a card, put that card into your hand, then shuffle.

Counter target spell. Its controller mills three cards.

Dismal Backwater enters the battlefield tapped.

When Dismal Backwater enters the battlefield, you gain 1 life.

{T}: Add {U} or {B}.

Drowned Catacomb enters the battlefield tapped unless you control an Island or a Swamp.

{T}: Add {U} or {B}.

Return all creatures to their owners' hands.

When Evangel of Synthesis enters the battlefield, draw a card, then discard a card.

As long as you've drawn two or more cards this turn, Evangel of Synthesis gets +1/+0 and has menace.

Flying

Eyekite gets +2/+0 as long as you've drawn two or more cards this turn.

Search your library for a card, put that card into your hand, then shuffle. You lose 3 life.

({T}: Add {U} or {B}.)

Ice Tunnel enters the battlefield tapped.

Whenever you cast a planeswalker spell, you gain 1 life.

{T}: Add {C}.

{1}, {T}: Add two mana of different colors. Spend this mana only to cast planeswalker spells.

Enchant creature

Enchanted creature can't be blocked except by Walls.

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

+2: Each player draws a card.

-1: Target player draws a card.

-10: Target player mills twenty cards.

Whenever you draw your second card each turn, put a +1/+1 counter on target creature you control.

+1: Draw a card.

-7: Creatures you control can't be blocked this turn.

+1: Draw a card.

+1: Untap all creatures you control.

-9: Gain control of up to three target creatures.

{T}, Sacrifice Jeweled Lotus: Add three mana of any one color. Spend this mana only to cast your commander.

Spells your opponents cast that target a creature or planeswalker you control cost {2} more to cast.

-2: Create a 2/2 blue Wizard creature token. Draw a card, then discard a card.

+1: Target player discards a card.

-2: Search your library for a card, then shuffle and put that card on top.

-8: Put all creature cards from all graveyards onto the battlefield under your control.

+1: Return up to one target creature card from your graveyard to your hand.

-3: Destroy target creature. Its controller loses 2 life.

-7: Target opponent loses 2 life for each creature card in their graveyard.

Morphic Pool enters the battlefield tapped unless you have two or more opponents.

{T}: Add {U} or {B}.

+1: Until your next turn, up to one target creature gets -5/-0.

-3: Return up to two target creatures to their owners' hands.

-7: Creatures you control with flying get +5/+5 until end of turn.

Whenever you cast an instant or sorcery spell, create a 1/1 blue Bird Illusion creature token with flying.

Flash (You may cast this spell any time you could cast an instant.)

Enchant creature

Whenever enchanted creature deals damage to an opponent, you may draw a card.

{T}: Add {U}.

Channel -- {3}{U}, Discard Otawara, Soaring City: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

Equipped creature gets +1/+0, has flying, and is a Bird in addition to its other types.

Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Whenever a creature you control deals combat damage to a player, you may draw a card.

Cycling {2} ({2}, Discard this card: Draw a card.)

(Gain the next level as a sorcery to add its ability.)

Whenever a creature you control deals combat damage to a player, exile the top card of that player's library face down. You may look at it for as long as it remains exiled.

{1}{U}{B}: Level 2

Creatures you control have menace.

{2}{U}{B}: Level 3

You may play cards exiled with Rogue Class, and you may spend mana as though it were mana of any color to cast those spells.

Shipwreck Marsh enters the battlefield tapped unless you control two or more other lands.

{T}: Add {U} or {B}.

{T}: Add {C}{C}.

{T}: Add {C}.

{U/B}, {T}: Add {U}{U}, {U}{B}, or {B}{B}.

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

{T}: Add {B}.

Channel -- {3}{B}, Discard Takenuma, Abandoned Mire: Mill three cards, then return a creature or planeswalker card from your graveyard to your hand. This ability costs {1} less to activate for each legendary creature you control.

Soulbond (You may pair this creature with another unpaired creature when either enters the battlefield. They remain paired for as long as you control both of them.)

As long as Tandem Lookout is paired with another creature, each of those creatures has "Whenever this creature deals damage to an opponent, draw a card."

You may activate loyalty abilities of Teferi, Master of Time on any player's turn any time you could cast an instant.

+1: Draw a card, then discard a card.

-3: Target creature you don't control phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.)

-10: Take two extra turns after this one.

Whenever you draw a card, put a loyalty counter on Teferi, Temporal Pilgrim.

0: Draw a card.

-2: Create a 2/2 blue Spirit creature token with vigilance and "Whenever you draw a card, put a +1/+1 counter on this creature."

-12: Target opponent chooses a permanent they control and returns it to its owner's hand. Then they shuffle each nonland permanent they control into its owner's library.

At the beginning of each end step, if a player discarded a card this turn, create a 1/1 black Bird creature token with flying and "This creature can't block."

{3}{B}, {T}: Each opponent discards a card. Activate only as a sorcery.

Flash

Thought Sponge enters the battlefield with a number of +1/+1 counters on it equal to the greatest number of cards an opponent has drawn this turn.

When Thought Sponge dies, draw cards equal to its power.

You have no maximum hand size.

{T}: Add {C}.

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

Compleated ({B/P} can be paid with {B} or 2 life. If life was paid, this planeswalker enters with two fewer loyalty counters.)

0: You draw a card and you lose 1 life. Proliferate.

-2: Target creature becomes a Treasure artifact with "{T}, Sacrifice this artifact: Add one mana of any color" and loses all other card types and abilities.

-9: If target player has fewer than nine poison counters, they get a number of poison counters equal to the difference.