Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Havoc Eater

Flying
When Havoc Eater enters the battlefield, for each opponent, goad up to one target creature that opponent controls. Put X +1/+1 counters on Havoc Eater, where X is the total power of creatures goaded this way.

Tyrant's Familiar

Flying, haste
Lieutenant — As long as you control your commander, Tyrant's Familiar gets +2/+2 and has "Whenever Tyrant's Familiar attacks, it deals 7 damage to target creature defending player controls."

Mountain

Mirror March

Whenever a nontoken creature enters the battlefield under your control, flip a coin until you lose a flip. For each flip you won, create a token that's a copy of that creature. Those tokens gain haste. Exile them at the beginning of the next end step.

Thunder Dragon

Flying
When Thunder Dragon enters the battlefield, it deals 3 damage to each creature without flying.

Sword of the Animist

Equipped creature gets +1/+1.
Whenever equipped creature attacks, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Equip {2}

Liquimetal Torque

{T}: Add {C}.
{T}: Target nonland permanent becomes an artifact in addition to its other types until end of turn.

Bloodlust Inciter

{T}: Target creature gains haste until end of turn.

Howling Mine

At the beginning of each player's draw step, if Howling Mine is untapped, that player draws an additional card.

Hazoret's Monument

Red creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, you may discard a card. If you do, draw a card.

Marauding Raptor

Creature spells you cast cost {1} less to cast.
Whenever another creature enters the battlefield under your control, Marauding Raptor deals 2 damage to it. If a Dinosaur is dealt damage this way, Marauding Raptor gets +2/+0 until end of turn.

Fellwar Stone

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

Resurrection Orb

Equipped creature has lifelink.
Whenever equipped creature dies, return that card to the battlefield under its owner's control at the beginning of the next end step.
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery.)

Kazuul, Tyrant of the Cliffs

Whenever a creature an opponent controls attacks, if you're the defending player, create a 3/3 red Ogre creature token unless that creature's controller pays {3}.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Combustible Gearhulk

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

Drakuseth, Maw of Flames

Flying
Whenever Drakuseth, Maw of Flames attacks, it deals 4 damage to any target and 3 damage to each of up to two other targets.

Magma Giant

When Magma Giant enters the battlefield, it deals 2 damage to each creature and each player.

Commander's Sphere

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

Fractured Powerstone

{T}: Add {C}.
{T}: Roll the planar die. Activate only as a sorcery.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Font of Mythos

At the beginning of each player's draw step, that player draws two additional cards.

Guild Feud

At the beginning of your upkeep, target opponent reveals the top three cards of their library, may put a creature card from among them onto the battlefield, then puts the rest into their graveyard. You do the same with the top three cards of your library. If two creatures are put onto the battlefield this way, those creatures fight each other.

Terror of Mount Velus

Flying, double strike
When Terror of Mount Velus enters the battlefield, creatures you control gain double strike until end of turn.

City on Fire

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
If a source you control would deal damage to a permanent or player, it deals triple that damage instead.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Mechanized Warfare

If a red or artifact source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 1 instead.

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Footfall Crater

Enchant land
Enchanted land has "{T}: Target creature gains trample and haste until end of turn."
Cycling {1} ({1}, Discard this card: Draw a card.)

Goblin Motivator

{T}: Target creature gains haste until end of turn. (It can attack and {T} this turn.)

Fire Dragon

Flying
When Fire Dragon enters the battlefield, it deals damage to target creature equal to the number of Mountains you control.

Lightning Greaves

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

Network Terminal

{T}: Add one mana of any color.
{1}, {T}, Tap another untapped artifact you control: Draw a card, then discard a card.

Sunbird's Invocation

Whenever you cast a spell from your hand, reveal the top X cards of your library, where X is that spell's mana value. You may cast a spell with mana value X or less from among cards revealed this way without paying its mana cost. Put the rest on the bottom of your library in a random order.

Tarrian's Soulcleaver

Equipped creature has vigilance.
Whenever another artifact or creature is put into a graveyard from the battlefield, put a +1/+1 counter on equipped creature.
Equip {2}

Neurok Hoversail

Equipped creature has flying.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery. This card enters the battlefield unattached and stays on the battlefield if the creature leaves.)

Burnished Hart

{3}, Sacrifice Burnished Hart: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Furnace of Rath

If a source would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Warstorm Surge

Whenever a creature enters the battlefield under your control, it deals damage equal to its power to any target.

Brash Taunter

Indestructible
Whenever Brash Taunter is dealt damage, it deals that much damage to target opponent.
{2}{R}, {T}: Brash Taunter fights another target creature.

Outrage Shaman

Chroma — When Outrage Shaman enters the battlefield, it deals damage to target creature equal to the number of red mana symbols in the mana costs of permanents you control.

Ilharg, the Raze-Boar

Trample
Whenever Ilharg, the Raze-Boar attacks, you may put a creature card from your hand onto the battlefield tapped and attacking. Return that creature to your hand at the beginning of the next end step.
When Ilharg, the Raze-Boar dies or is put into exile from the battlefield, you may put it into its owner's library third from the top.

Utvara Hellkite

Flying
Whenever a Dragon you control attacks, create a 6/6 red Dragon creature token with flying.

Reliquary Tower

Chaos Maw

When Chaos Maw enters the battlefield, it deals 3 damage to each other creature.

Ruby Medallion

Red spells you cast cost {1} less to cast.

Might Makes Right

At the beginning of combat on your turn, if you control each creature on the battlefield with the greatest power, gain control of target creature an opponent controls until end of turn. Untap that creature. It gains haste until end of turn. (It can attack and {T} this turn.)

Red Dragon

Flying
Fire Breath — When Red Dragon enters the battlefield, it deals 4 damage to each opponent.

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Geode Rager

First strike
Landfall — Whenever a land enters the battlefield under your control, goad each creature target player controls. (Until your next turn, those creatures attack each combat if able and attack a player other than you if able.)

Axgard Cavalry

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Rage Reflection

Creatures you control have double strike.

Arcane Signet

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

Zephyr Boots

Equipped creature has flying.
Whenever equipped creature deals combat damage to a player, draw a card, then discard a card.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Flamerush Rider

Whenever Flamerush Rider attacks, create a token that's a copy of another target attacking creature and that's tapped and attacking. Exile the token at end of combat.
Dash {2}{R}{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.)

Spawn of Thraxes

Flying
When Spawn of Thraxes enters the battlefield, it deals damage to any target equal to the number of Mountains you control.

Thundermare

Haste (This creature can attack and {T} as soon as it comes under your control.)
When Thundermare enters the battlefield, tap all other creatures.

Myriad Landscape

Myriad Landscape enters the battlefield tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Racecourse Fury

Enchant land
Enchanted land has "{T}: Target creature gains haste until end of turn."

Sol Ring

Disrupt Decorum

Goad all creatures you don't control. (Until your next turn, those creatures attack each combat if able and attack a player other than you if able.)