Prioritize 

Diabolic Intent

As an additional cost to cast this spell, sacrifice a creature.
Search your library for a card, put that card into your hand, then shuffle.

Polluted Delta

{T}, Pay 1 life, Sacrifice Polluted Delta: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Have

Orcish Bowmasters

Flash
When Orcish Bowmasters enters and whenever an opponent draws a card except the first one they draw in each of their draw steps, Orcish Bowmasters deals 1 damage to any target. Then amass Orcs 1.

Agatha's Soul Cauldron

You may spend mana as though it were mana of any color to activate abilities of creatures you control.
Creatures you control with +1/+1 counters on them have all activated abilities of all creature cards exiled with Agatha's Soul Cauldron.
{T}: Exile target card from a graveyard. When a creature card is exiled this way, put a +1/+1 counter on target creature you control.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Gut Shot

({R/P} can be paid with either {R} or 2 life.)
Gut Shot deals 1 damage to any target.

City of Brass

Whenever City of Brass becomes tapped, it deals 1 damage to you.
{T}: Add one mana of any color.

Urza's Saga

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Urza's Saga gains "{T}: Add {C}."
II — Urza's Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This creature gets +1/+1 for each artifact you control.'"
III — Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.

Wooded Foothills

{T}, Pay 1 life, Sacrifice Wooded Foothills: Search your library for a Mountain or Forest card, put it onto the battlefield, then shuffle.

Razorkin Needlehead

Razorkin Needlehead has first strike during your turn.
Whenever an opponent draws a card, Razorkin Needlehead deals 1 damage to them.

Snuff Out

If you control a Swamp, you may pay 4 life rather than pay this spell's mana cost.
Destroy target nonblack creature. It can't be regenerated.

Pyroblast

Choose one —
• Counter target spell if it's blue.
• Destroy target permanent if it's blue.

Bloodstained Mire

{T}, Pay 1 life, Sacrifice Bloodstained Mire: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Mox Amber

{T}: Add one mana of any color among legendary creatures and planeswalkers you control.

Sulfurous Springs

{T}: Add {C}.
{T}: Add {B} or {R}. Sulfurous Springs deals 1 damage to you.

Walking Ballista

Walking Ballista enters with X +1/+1 counters on it.
{4}: Put a +1/+1 counter on Walking Ballista.
Remove a +1/+1 counter from Walking Ballista: It deals 1 damage to any target.

Ancient Tomb

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

Simian Spirit Guide

Exile Simian Spirit Guide from your hand: Add {R}.

Verdant Catacombs

{T}, Pay 1 life, Sacrifice Verdant Catacombs: Search your library for a Swamp or Forest card, put it onto the battlefield, then shuffle.

Gleeful Arsonist

Whenever an opponent casts a noncreature spell, Gleeful Arsonist deals damage equal to its power to that player.
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Badlands

Defense Grid

Each spell costs {3} more to cast except during its controller's turn.

Gemstone Caverns

If Gemstone Caverns is in your opening hand and you're not the starting player, you may begin the game with Gemstone Caverns on the battlefield with a luck counter on it. If you do, exile a card from your hand.
{T}: Add {C}. If Gemstone Caverns has a luck counter on it, instead add one mana of any color.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Red Elemental Blast

Choose one —
• Counter target blue spell.
• Destroy target blue permanent.

Mox Opal

Metalcraft — {T}: Add one mana of any color. Activate only if you control three or more artifacts.

Gamble

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

Ob Nixilis, Captive Kingpin

Flying, trample
Whenever one or more opponents each lose exactly 1 life, put a +1/+1 counter on Ob Nixilis, Captive Kingpin. Exile the top card of your library. Until your next end step, you may play that card.

Goblin Engineer

When Goblin Engineer enters, you may search your library for an artifact card, put it into your graveyard, then shuffle.
{R}, {T}, Sacrifice an artifact: Return target artifact card with mana value 3 or less from your graveyard to the battlefield.

Chrome Mox

Imprint — When Chrome Mox enters, you may exile a nonartifact, nonland card from your hand.
{T}: Add one mana of any of the exiled card's colors.

Prismatic Vista

{T}, Pay 1 life, Sacrifice Prismatic Vista: Search your library for a basic land card, put it onto the battlefield, then shuffle.

Demonic Counsel

Search your library for a Demon card, reveal it, put it into your hand, then shuffle.
Delirium — If there are four or more card types among cards in your graveyard, instead search your library for any card, put it into your hand, then shuffle.

Demonic Tutor

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

Scalding Tarn

{T}, Pay 1 life, Sacrifice Scalding Tarn: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

Rite of Flame

Add {R}{R}, then add {R} for each card named Rite of Flame in each graveyard.

Yawgmoth's Will

Until end of turn, you may play lands and cast spells from your graveyard.
If a card would be put into your graveyard from anywhere this turn, exile that card instead.

Untimely Malfunction

Choose one —
• Destroy target artifact.
• Change the target of target spell or ability with a single target.
• One or two target creatures can't block this turn.

Scrawling Crawler

At the beginning of your upkeep, each player draws a card.
Whenever an opponent draws a card, that player loses 1 life.

Underworld Breach

Each nonland card in your graveyard has escape. The escape cost is equal to the card's mana cost plus exile three other cards from your graveyard. (You may cast cards from your graveyard for their escape cost.)
At the beginning of the end step, sacrifice Underworld Breach.

Blazemire Verge

{T}: Add {B}.
{T}: Add {R}. Activate only if you control a Swamp or a Mountain.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Kederekt Parasite

Whenever an opponent draws a card, if you control a red permanent, you may have Kederekt Parasite deal 1 damage to that player.

Wishclaw Talisman

This artifact enters with three wish counters on it.
{1}, {T}, Remove a wish counter from this artifact: Search your library for a card, put it into your hand, then shuffle. An opponent gains control of this artifact. Activate only during your turn.

Bolas's Citadel

You may look at the top card of your library any time.
You may play lands and cast spells from the top of your library. If you cast a spell this way, pay life equal to its mana value rather than pay its mana cost.
{T}, Sacrifice ten nonland permanents: Each opponent loses 10 life.

Swamp

Deadly Rollick

If you control a commander, you may cast this spell without paying its mana cost.
Exile target creature.

Arid Mesa

{T}, Pay 1 life, Sacrifice Arid Mesa: Search your library for a Mountain or Plains card, put it onto the battlefield, then shuffle.

Sensei's Divining Top

{1}: Look at the top three cards of your library, then put them back in any order.
{T}: Draw a card, then put Sensei's Divining Top on top of its owner's library.

Ragavan, Nimble Pilferer

Whenever Ragavan, Nimble Pilferer deals combat damage to a player, create a Treasure token and exile the top card of that player's library. Until end of turn, you may cast that card.
Dash {1}{R} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)

Talisman of Indulgence

{T}: Add {C}.
{T}: Add {B} or {R}. Talisman of Indulgence deals 1 damage to you.

Mana Vault

Mana Vault doesn't untap during your untap step.
At the beginning of your upkeep, you may pay {4}. If you do, untap Mana Vault.
At the beginning of your draw step, if Mana Vault is tapped, it deals 1 damage to you.
{T}: Add {C}{C}{C}.

Mana Confluence

{T}, Pay 1 life: Add one mana of any color.

Tibalt's Trickery

Counter target spell. Choose 1, 2, or 3 at random. Its controller mills that many cards, then exiles cards from the top of their library until they exile a nonland card with a different name than that spell. They may cast that card without paying its mana cost. Then they put the exiled cards on the bottom of their library in a random order.

Sol Ring

Searstep Pathway

Blightstep Pathway

Blightstep Pathway // Searstep Pathway

Prosper, Tome-Bound

Deathtouch
Mystic Arcanum — At the beginning of your end step, exile the top card of your library. Until the end of your next turn, you may play that card.
Pact Boon — Whenever you play a card from exile, create a Treasure token.

Imp's Mischief

Change the target of target spell with a single target. You lose life equal to that spell's mana value.

Vampiric Tutor

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

Takenuma, Abandoned Mire

{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.

Reckless Fireweaver

Whenever an artifact you control enters, Reckless Fireweaver deals 1 damage to each opponent.

Dismember

({B/P} can be paid with either {B} or 2 life.)
Target creature gets -5/-5 until end of turn.

Firebrand Archer

Whenever you cast a noncreature spell, this creature deals 1 damage to each opponent.

Pyretic Ritual

Cabal Ritual

Add {B}{B}{B}.
Threshold — Add {B}{B}{B}{B}{B} instead if seven or more cards are in your graveyard.

Mountain

Fire Covenant

As an additional cost to cast this spell, pay X life.
Fire Covenant deals X damage divided as you choose among any number of target creatures.

Luxury Suite

Luxury Suite enters tapped unless you have two or more opponents.
{T}: Add {B} or {R}.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Unstable Amulet

When Unstable Amulet enters, you get {E}{E} (two energy counters).
Whenever you cast a spell from anywhere other than your hand, Unstable Amulet deals 1 damage to each opponent.
{T}, Pay {E}{E}: Exile the top card of your library. You may play it until you exile another card with Unstable Amulet.

Bolt Bend

This spell costs {3} less to cast if you control a creature with power 4 or greater.
Change the target of target spell or ability with a single target.

Kessig Flamebreather

Whenever you cast a noncreature spell, Kessig Flamebreather deals 1 damage to each opponent.

Arcane Signet

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

Abrade

Choose one —
• Abrade deals 3 damage to target creature.
• Destroy target artifact.

Desperate Ritual

Add {R}{R}{R}.
Splice onto Arcane {1}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Raucous Theater

({T}: Add {B} or {R}.)
Raucous Theater enters tapped.
When Raucous Theater enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Imperial Seal

Imperial Recruiter

When Imperial Recruiter enters, search your library for a creature card with power 2 or less, reveal it, put it into your hand, then shuffle.

Blood Crypt

({T}: Add {B} or {R}.)
As Blood Crypt enters, you may pay 2 life. If you don't, it enters tapped.

The One Ring

Indestructible
When The One Ring enters, if you cast it, you gain protection from everything until your next turn.
At the beginning of your upkeep, you lose 1 life for each burden counter on The One Ring.
{T}: Put a burden counter on The One Ring, then draw a card for each burden counter on The One Ring.

Beseech the Mirror

Bargain (You may sacrifice an artifact, enchantment, or token as you cast this spell.)
Search your library for a card, exile it face down, then shuffle. If this spell was bargained, you may cast the exiled card without paying its mana cost if that spell's mana value is 4 or less. Put the exiled card into your hand if it wasn't cast this way.

Phyrexian Tower

{T}: Add {C}.
{T}, Sacrifice a creature: Add {B}{B}.

All Will Be One

Whenever you put one or more counters on a permanent or player, All Will Be One deals that much damage to target opponent, creature an opponent controls, or planeswalker an opponent controls.

Exotic Orchard

Deflecting Swat

If you control a commander, you may cast this spell without paying its mana cost.
You may choose new targets for target spell or ability.

Jeska's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Add {R} for each card in target opponent's hand.
• Exile the top three cards of your library. You may play them this turn.

Party Thrasher

Noncreature spells you cast from exile have convoke. (Each creature you tap while casting a noncreature spell from exile pays for {1} or one mana of that creature's color.)
At the beginning of your first main phase, you may discard a card. If you do, exile the top two cards of your library, then choose one of them. You may play that card this turn.

Grapeshot

Grapeshot deals 1 damage to any target.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Roiling Vortex

At the beginning of each player's upkeep, Roiling Vortex deals 1 damage to them.
Whenever a player casts a spell, if no mana was spent to cast that spell, Roiling Vortex deals 5 damage to that player.
{R}: Your opponents can't gain life this turn.

Coruscation Mage

Offspring {2} (You may pay an additional {2} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
Whenever you cast a noncreature spell, this creature deals 1 damage to each opponent.

Dauthi Voidwalker

Shadow (This creature can block or be blocked by only creatures with shadow.)
If a card would be put into an opponent's graveyard from anywhere, instead exile it with a void counter on it.
{T}, Sacrifice Dauthi Voidwalker: Choose an exiled card an opponent owns with a void counter on it. You may play it this turn without paying its mana cost.

Spire of Industry

{T}: Add {C}.
{T}, Pay 1 life: Add one mana of any color. Activate only if you control an artifact.

Lotus Petal

{T}, Sacrifice Lotus Petal: Add one mana of any color.

Marsh Flats

{T}, Pay 1 life, Sacrifice Marsh Flats: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

Harnfel, Horn of Bounty

Discard a card: Exile the top two cards of your library. You may play those cards this turn.

Birgi, God of Storytelling

Whenever you cast a spell, add {R}. Until end of turn, you don't lose this mana as steps and phases end.
Creatures you control can boast twice during each of your turns rather than once.

Birgi, God of Storytelling // Harnfel, Horn of Bounty

Command Tower

Culling the Weak

As an additional cost to cast this spell, sacrifice a creature.
Add {B}{B}{B}{B}.

Mount Doom

{T}, Pay 1 life: Add {B} or {R}.
{1}{B}{R}, {T}: Mount Doom deals 1 damage to each opponent.
{5}{B}{R}, {T}, Sacrifice Mount Doom and a legendary artifact: Choose up to two creatures, then destroy the rest. Activate only as a sorcery.