Circle of Flame

Whenever a creature without flying attacks you or a planeswalker you control, Circle of Flame deals 1 damage to that creature.

Berserkers' Onslaught

Attacking creatures you control have double strike.

Cavalcade of Calamity

Whenever a creature you control with power 1 or less attacks, Cavalcade of Calamity deals 1 damage to the player or planeswalker that creature is attacking.

Brazen Scourge

Haste (This creature can attack and {T} as soon as it comes under your control.)

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Purphoros, God of the Forge

Indestructible
As long as your devotion to red is less than five, Purphoros isn't a creature.
Whenever another creature you control enters, Purphoros deals 2 damage to each opponent.
{2}{R}: Creatures you control get +1/+0 until end of turn.

Ball Lightning

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Haste (This creature can attack and {T} as soon as it comes under your control.)
At the beginning of the end step, sacrifice this creature.

Besmirch

Until end of turn, gain control of target creature and it gains haste. Untap and goad that creature. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)

Where Ancients Tread

Whenever a creature you control with power 5 or greater enters, you may have Where Ancients Tread deal 5 damage to any target.

Pandemonium

Whenever a creature enters, that creature's controller may have it deal damage equal to its power to any target of their choice.

Warstorm Surge

Whenever a creature you control enters, it deals damage equal to its power to any target.

Barbed Shocker

Trample, haste
Whenever Barbed Shocker deals damage to a player, that player discards all the cards in their hand, then draws that many cards.

Akroma's Memorial

Creatures you control have flying, first strike, vigilance, trample, haste, and protection from black and from red.

Avatar of Slaughter

All creatures have double strike and attack each combat if able.

Fiendish Duo

First strike (This creature deals combat damage before creatures without first strike.)
If a source would deal damage to an opponent, it deals double that damage to that player instead.

Ambush Party

Dictate of the Twin Gods

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

Awaken the Ancient

Enchant Mountain
Enchanted Mountain is a 7/7 red Giant creature with haste. It's still a land.

Boots of Speed

Equipped creature gets +1/+0 and has haste.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Impact Resonance

Impact Resonance deals X damage divided as you choose among any number of target creatures, where X is the greatest amount of damage dealt by a source to a permanent or player this turn.

Great Train Heist

Spree (Choose one or more additional costs.)
+ {2}{R} — Untap all creatures you control. If it's your combat phase, there is an additional combat phase after this phase.
+ {2} — Creatures you control get +1/+0 and gain first strike until end of turn.
+ {R} — Choose target opponent. Whenever a creature you control deals combat damage to that player this turn, create a tapped Treasure token.

Arni Metalbrow

Whenever a creature you control attacks or a creature you control enters attacking, you may pay {1}{R}. If you do, you may put a creature card with mana value less than that creature's mana value from your hand onto the battlefield tapped and attacking.

Calamity Bearer

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

Rage Reflection

Creatures you control have double strike.

Grenzo, Havoc Raiser

Whenever a creature you control deals combat damage to a player, choose one —
• Goad target creature that player controls.
• Exile the top card of that player's library. Until end of turn, you may cast that card and you may spend mana as though it were mana of any color to cast that spell.

Fire Servant

If a red instant or sorcery spell you control would deal damage, it deals double that damage instead.

Altar of the Goyf

Whenever a creature you control attacks alone, it gets +X/+X until end of turn, where X is the number of card types among cards in all graveyards.
Lhurgoyf creatures you control have trample.

Awaken the Sleeper

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. If it's equipped, you may destroy all Equipment attached to that creature.

Chariot of Victory

Equipped creature has first strike, trample, and haste.
Equip {1}

Breakneck Berserker

Curse of Bloodletting

Enchant player
If a source would deal damage to enchanted player, it deals double that damage to that player instead.

Close Quarters

Whenever a creature you control becomes blocked, Close Quarters deals 1 damage to any target.

Fiery Emancipation

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

Anger

Haste
As long as Anger is in your graveyard and you control a Mountain, creatures you control have haste.

Repercussion

Whenever a creature is dealt damage, Repercussion deals that much damage to that creature's controller.

Curse of Hospitality

Enchant player
Creatures attacking enchanted player have trample.
Whenever a creature deals combat damage to enchanted player, that player exiles the top card of their library. Until end of turn, that creature's controller may play that card and they may spend mana as though it were mana of any color to cast that spell.

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.

Injury

Aftermath (Cast this spell only from your graveyard. Then exile it.)
Injury deals 2 damage to target creature and 2 damage to target player or planeswalker.

Insult

Damage can't be prevented this turn. If a source you control would deal damage this turn, it deals double that damage instead.

Insult // Injury

Battle Strain

Whenever a creature blocks, Battle Strain deals 1 damage to that creature's controller.

In the Web of War

Whenever a creature you control enters, it gets +2/+0 and gains haste until end of turn.

Doubling Cube

{3}, {T}: Double the amount of each type of unspent mana you have.

Inquisitor's Flail

If equipped creature would deal combat damage, it deals double that damage instead.
If another creature would deal combat damage to equipped creature, it deals double that damage to equipped creature instead.
Equip {2}