Getting

Manabarbs

Whenever a player taps a land for mana, Manabarbs deals 1 damage to that player.

Don't Have

Earthquake

Earthquake deals X damage to each creature without flying and each player.

Spellshock

Whenever a player casts a spell, Spellshock deals 2 damage to that player.

Fanatic of Mogis

When Fanatic of Mogis enters, it deals damage to each opponent equal to your devotion to red. (Each {R} in the mana costs of permanents you control counts toward your devotion to red.)

Prisoner's Dilemma

Each opponent secretly chooses silence or snitch, then the choices are revealed. If each opponent chose silence, Prisoner's Dilemma deals 4 damage to each of them. If each opponent chose snitch, Prisoner's Dilemma deals 8 damage to each of them. Otherwise, Prisoner's Dilemma deals 12 damage to each opponent who chose silence.
Flashback {5}{R}{R}

Pyrostatic Pillar

Whenever a player casts a spell with mana value 3 or less, Pyrostatic Pillar deals 2 damage to that player.

Pristine Talisman

Citadel of Pain

At the beginning of each player's end step, Citadel of Pain deals X damage to that player, where X is the number of untapped lands they control.

Abrade

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

Bottle Gnomes

Sacrifice Bottle Gnomes: You gain 3 life.

Outpost Siege

As Outpost Siege enters, choose Khans or Dragons.
• Khans — At the beginning of your upkeep, exile the top card of your library. Until end of turn, you may play that card.
• Dragons — Whenever a creature you control leaves the battlefield, Outpost Siege deals 1 damage to any target.

Firedrinker Satyr

Whenever Firedrinker Satyr is dealt damage, it deals that much damage to you.
{1}{R}: Firedrinker Satyr gets +1/+0 until end of turn and deals 1 damage to you.

Heartless Hidetsugu

{T}: Heartless Hidetsugu deals damage to each player equal to half that player's life total, rounded down.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

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.

Endless Atlas

{2}, {T}: Draw a card. Activate only if you control three or more lands with the same name.

Koth, Fire of Resistance

+2: Search your library for a basic Mountain card, reveal it, put it into your hand, then shuffle.
−3: Koth, Fire of Resistance deals damage to target creature equal to the number of Mountains you control.
−7: You get an emblem with "Whenever a Mountain you control enters, this emblem deals 4 damage to any target."

Patriar's Seal

{T}: Add one mana of any color.
{1}, {T}: Untap target legendary creature you control.

Platinum Angel

Flying
You can't lose the game and your opponents can't win the game.

Arcane Signet

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

Harsh Mentor

Whenever an opponent activates an ability of an artifact, creature, or land on the battlefield, if it isn't a mana ability, Harsh Mentor deals 2 damage to that player.

Goblin Researcher

When Goblin Researcher enters, exile the top card of your library. During any turn you attacked with Goblin Researcher, you may play that card.

Act on Impulse

Exile the top three cards of your library. Until end of turn, you may play those cards. (If you cast a spell this way, you still pay its costs. You can play a land this way only if you have an available land play remaining.)

Spinerock Knoll

Hideaway 4 (When this land enters, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)
Spinerock Knoll enters tapped.
{T}: Add {R}.
{R}, {T}: You may play the exiled card without paying its mana cost if an opponent was dealt 7 or more damage this turn.

Power Surge

At the beginning of each player's upkeep, Power Surge deals X damage to that player, where X is the number of untapped lands they controlled at the beginning of this turn.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Rug of Smothering

Flying
Whenever a player casts a spell, they lose 1 life for each spell they've cast this turn.

Risk Factor

Target opponent may have Risk Factor deal 4 damage to them. If that player doesn't, you draw three cards.
Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)

Fortune Thief

Damage that would reduce your life total to less than 1 reduces it to 1 instead.
Morph {R}{R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Fiendlash

Equipped creature gets +2/+0 and has reach.
Whenever equipped creature is dealt damage, it deals damage equal to its power to target player or planeswalker.
Equip {2}{R}

Fellwar Stone

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

Enchanter's Bane

At the beginning of your end step, target enchantment deals damage equal to its mana value to its controller unless that player sacrifices it.

Fling

As an additional cost to cast this spell, sacrifice a creature.
Fling deals damage equal to the sacrificed creature's power to any target.

Auntie Blyte, Bad Influence

Flying
Whenever a source you control deals damage to you, put that many +1/+1 counters on Auntie Blyte, Bad Influence.
{1}{R}, {T}, Remove X +1/+1 counters from Auntie Blyte: It deals X damage to any target.

Jackal Pup

Whenever Jackal Pup is dealt damage, it deals that much damage to you.

Stuffy Doll

Indestructible
As Stuffy Doll enters, choose a player.
Whenever Stuffy Doll is dealt damage, it deals that much damage to the chosen player.
{T}: Stuffy Doll deals 1 damage to itself.

Goblin Artillery

{T}: Goblin Artillery deals 2 damage to any target and 3 damage to you.

Scavenged Brawler

Flying, vigilance, trample, lifelink
{5}, Exile Scavenged Brawler from your graveyard: Choose target creature. Put four +1/+1 counters, a flying counter, a vigilance counter, a trample counter, and a lifelink counter on that creature. Activate only as a sorcery.

Sol Ring

Chandra, Fire Artisan

Whenever one or more loyalty counters are removed from Chandra, Fire Artisan, she deals that much damage to target opponent or planeswalker.
+1: Exile the top card of your library. You may play it this turn.
−7: Exile the top seven cards of your library. You may play them this turn.

Commune with Lava

Exile the top X cards of your library. Until the end of your next turn, you may play those cards.

Have

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.

Madcap Experiment

Reveal cards from the top of your library until you reveal an artifact card. Put that card onto the battlefield and the rest on the bottom of your library in a random order. Madcap Experiment deals damage to you equal to the number of cards revealed this way.

Orcish Artillery

{T}: Orcish Artillery deals 2 damage to any target and 3 damage to you.

Platinum Emperion

Your life total can't change. (You can't gain or lose life. You can't pay any amount of life except 0.)

Scytheclaw Raptor

Whenever a player casts a spell, if it's not their turn, Scytheclaw Raptor deals 4 damage to them.

Burning Earth

Whenever a player taps a nonbasic land for mana, Burning Earth deals 1 damage to that player.

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.)

Grafted Exoskeleton

Equipped creature gets +2/+2 and has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Whenever Grafted Exoskeleton becomes unattached from a permanent, sacrifice that permanent.
Equip {2}

Chain of Plasma

Chain of Plasma deals 3 damage to any target. Then that player or that permanent's controller may discard a card. If the player does, they may copy this spell and may choose a new target for that copy.

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.

Dragon's Claw

Whenever a player casts a red spell, you may gain 1 life.

Reckless Impulse

Exile the top two cards of your library. Until the end of your next turn, you may play those cards.

Kediss, Emberclaw Familiar

Whenever a commander you control deals combat damage to an opponent, it deals that much damage to each other opponent.
Partner (You can have two commanders if both have partner.)

Hammerfist Giant

{T}: Hammerfist Giant deals 4 damage to each creature without flying and each player.

Sun Droplet

Whenever you're dealt damage, put that many charge counters on Sun Droplet.
At the beginning of each upkeep, you may remove a charge counter from Sun Droplet. If you do, you gain 1 life.

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.)

Mountain

Molten Disaster

Kicker {R} (You may pay an additional {R} as you cast this spell.)
If this spell was kicked, it has split second. (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Molten Disaster deals X damage to each creature without flying and each player.

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Orcish Cannoneers

{T}: Orcish Cannoneers deals 2 damage to any target and 3 damage to you.

Browbeat

Any player may have Browbeat deal 5 damage to them. If no one does, target player draws three cards.

Exocrine

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Bio-plasmic Barrage — When Exocrine enters, it deals X damage to each player and each other creature.

Runaway Steam-Kin

Whenever you cast a red spell, if Runaway Steam-Kin has fewer than three +1/+1 counters on it, put a +1/+1 counter on Runaway Steam-Kin.
Remove three +1/+1 counters from Runaway Steam-Kin: Add {R}{R}{R}.

Staff of the Flame Magus

Whenever you cast a red spell or a Mountain you control enters, you gain 1 life.

Anzrag's Rampage

Destroy all artifacts you don't control, then exile the top X cards of your library, where X is the number of artifacts that were put into graveyards from the battlefield this turn. You may put a creature card exiled this way onto the battlefield. It gains haste. Return it to your hand at the beginning of the next end step.

Light Up the Stage

Spectacle {R} (You may cast this spell for its spectacle cost rather than its mana cost if an opponent lost life this turn.)
Exile the top two cards of your library. Until the end of your next turn, you may play those cards.

Chain Reaction

Chain Reaction deals X damage to each creature, where X is the number of creatures on the battlefield.