Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Combat Courier

{2}, Sacrifice this creature: Draw a card.
Unearth {U} ({U}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Eldrazi Skyspawner

Devoid (This card has no color.)
Flying
When this creature enters, create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this token: Add {C}."

The Surgical Bay

This land enters tapped.
{T}: Add {U}.
{1}{U}, {T}, Sacrifice this land: Draw a card.

Spiketail Hatchling

Flying (This creature can't be blocked except by creatures with flying or reach.)
Sacrifice this creature: Counter target spell unless its controller pays {1}.

Haunted Fengraf

{T}: Add {C}.
{3}, {T}, Sacrifice this land: Return a creature card at random from your graveyard to your hand.

Workshop Assistant

When this creature dies, return another target artifact card from your graveyard to your hand.

Ashnod's Altar

Fade Away

For each creature, its controller sacrifices a permanent of their choice unless they pay {1}.

Filigree Familiar

When this creature enters, you gain 2 life.
When this creature dies, draw a card.

Jace's Erasure

Whenever you draw a card, you may have target player mill a card.

Hapless Researcher

Sacrifice this creature: Draw a card, then discard a card.

Teardrop Kami

Sacrifice this creature: You may tap or untap target creature.

Sidisi's Faithful

Exploit (When this creature enters, you may sacrifice a creature.)
When this creature exploits a creature, return target creature to its owner's hand.

Impaler Shrike

Flying
Whenever this creature deals combat damage to a player, you may sacrifice it. If you do, draw three cards.

Inga Rune-Eyes

When Inga Rune-Eyes enters, scry 3.
When Inga Rune-Eyes dies, draw three cards if three or more creatures died this turn.

Oculus

When this creature dies, you may draw a card.

Perilous Research

Draw two cards, then sacrifice a permanent.

Living Lectern

{1}, Sacrifice this creature: Draw a card. Create a Sorcerer Role token attached to up to one other target creature you control. Activate only as a sorcery. (If you control another Role on it, put that one into the graveyard. Enchanted creature gets +1/+1 and has "Whenever this creature attacks, scry 1.")

Ghostly Flicker

Exile two target artifacts, creatures, and/or lands you control, then return those cards to the battlefield under your control.

Seafloor Stalker

{4}{U}: This creature gets +1/+0 until end of turn and can't be blocked this turn. This ability costs {1} less to activate for each creature in your party. (Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.)

Cephalid Pathmage

This creature can't be blocked.
{T}, Sacrifice this creature: Target creature can't be blocked this turn.

Spiketail Drakeling

Flying
Sacrifice this creature: Counter target spell unless its controller pays {2}.

Repository Skaab

Exploit (When this creature enters, you may sacrifice a creature.)
When this creature exploits a creature, return target instant or sorcery card from your graveyard to your hand.

Cephalid Snitch

Sacrifice this creature: Target creature loses protection from black until end of turn.

Unfathomable Truths

Devoid (This card has no color.)
Draw three cards and create a 0/1 colorless Eldrazi Spawn creature token with "Sacrifice this token: Add {C}."

Treasure Cruise

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Draw three cards.

Abstruse Interference

Devoid (This card has no color.)
Counter target spell unless its controller pays {1}. You create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this token: Add {C}." ({C} represents colorless mana.)

Make Disappear

Casualty 1 (As you cast this spell, you may sacrifice a creature with power 1 or greater. When you do, copy this spell and you may choose a new target for the copy.)
Counter target spell unless its controller pays {2}.

Vivisection

As an additional cost to cast this spell, sacrifice a creature.
Draw three cards.

Hydromorph Guardian

{U}, Sacrifice this creature: Counter target spell that targets a creature you control.

Alchemist's Apprentice

Myr Scrapling

Sacrifice this creature: Put a +1/+1 counter on target creature.

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Eidolon of Philosophy

{6}{U}, Sacrifice this creature: Draw three cards.

Neurok Replica

{1}{U}, Sacrifice this creature: Return target creature to its owner's hand.

Arcane Signet

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

Aura Flux

Other enchantments have "At the beginning of your upkeep, sacrifice this enchantment unless you pay {2}."

Abjure

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

Enigma Eidolon

{U}, Sacrifice this creature: Target player mills three cards.
Whenever you cast a multicolored spell, you may return this card from your graveyard to your hand.

Island

Stitcher's Apprentice

{1}{U}, {T}: Create a 2/2 blue Homunculus creature token, then sacrifice a creature.

Sky Diamond

This artifact enters tapped.
{T}: Add {U}.

Mulldrifter

Flying
When this creature enters, draw two cards.
Evoke {2}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Sage's Row Denizen

Whenever another blue creature you control enters, target player mills two cards.

Parcel Myr

{2}, Sacrifice this creature: Draw a card.

Counterspell

Negate

Wayfarer's Bauble

{2}, {T}, Sacrifice this artifact: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Bury in Books

This spell costs {2} less to cast if it targets an attacking creature.
Put target creature into its owner's library second from the top.

Wizard Replica

Flying
{U}, Sacrifice this creature: Counter target spell unless its controller pays {2}.

Drake Familiar

Flying
When this creature enters, sacrifice it unless you return an enchantment to its owner's hand.

Aven Augur

Flying
Sacrifice this creature: Return up to two target creatures to their owners' hands. Activate only during your upkeep.

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Displace

Exile up to two target creatures you control, then return those cards to the battlefield under their owner's control.

Stitched Assistant

Exploit (When this creature enters, you may sacrifice a creature.)
When this creature exploits a creature, scry 1, then draw a card. (To scry 1, look at the top card of your library, then you may put that card on the bottom.)

Brainstorm

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

Pendrell Flux

Enchant creature
Enchanted creature has "At the beginning of your upkeep, sacrifice this creature unless you pay its mana cost."

Sarcomite Myr

{2}: This creature gains flying until end of turn.
{2}, Sacrifice this creature: Draw a card.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice this artifact: Draw a card.

Scribe of the Mindful

{1}, {T}, Sacrifice this creature: Return target instant or sorcery card from your graveyard to your hand.

Salvage Drone

Devoid (This card has no color.)
Ingest (Whenever this creature deals combat damage to a player, that player exiles the top card of their library.)
When this creature dies, you may draw a card. If you do, discard a card.

Rotcrown Ghoul

When this creature dies, target player mills five cards.

Bottle Gnomes

Sacrifice this creature: You gain 3 life.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Incubator Drone

Devoid (This card has no color.)
When this creature enters, create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this token: Add {C}."

Merchant Scroll

Search your library for a blue instant card, reveal that card, put it into your hand, then shuffle.

Cathodion

Drownyard Lurker

Vigilance
When you cast or cycle Drownyard Lurker, create a 0/1 colorless Eldrazi Spawn creature token with "Sacrifice this token: Add {C}."
Cycling {2}{U} ({2}{U}, Discard this card: Draw a card.)