Witty Roastmaster

Alliance — Whenever another creature enters the battlefield under your control, Witty Roastmaster deals 1 damage to each opponent.

Panharmonicon

If an artifact or creature entering the battlefield causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Terror of the Peaks

Flying
Spells your opponents cast that target Terror of the Peaks cost an additional 3 life to cast.
Whenever another creature enters the battlefield under your control, Terror of the Peaks deals damage equal to that creature's power to any target.

Irencrag Feat

Add seven {R}. You can cast only one more spell this turn.

Torbran, Thane of Red Fell

If a red source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 2 instead.

Chef's Kiss

Gain control of target spell that targets only a single permanent or player. Copy it, then reselect the targets at random for the spell and the copy. The new targets can't be you or a permanent you control.

Iron Myr

Wild Ricochet

You may choose new targets for target instant or sorcery spell. Then copy that spell. You may choose new targets for the copy.

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.

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.

Plargg and Nassari

At the beginning of your upkeep, each player exiles cards from the top of their library until they exile a nonland card. An opponent chooses a nonland card exiled this way. You may cast up to two spells from among the other cards exiled this way without paying their mana costs.

Hero's Blade

Equipped creature gets +3/+2.
Whenever a legendary creature enters the battlefield under your control, you may attach Hero's Blade to it.
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery.)

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 enters the battlefield under your control, Purphoros deals 2 damage to each opponent.
{2}{R}: Creatures you control get +1/+0 until end of turn.

Genesis Chamber

Whenever a nontoken creature enters the battlefield, if Genesis Chamber is untapped, that creature's controller creates a 1/1 colorless Myr artifact creature token.

Gamble

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

Possibility Storm

Whenever a player casts a spell from their hand, that player exiles it, then exiles cards from the top of their library until they exile a card that shares a card type with it. That player may cast that card without paying its mana cost. Then they put all cards exiled with Possibility Storm on the bottom of their library in a random order.

Solemn Simulacrum

When Solemn Simulacrum enters the battlefield, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

Obsidian Battle-Axe

Equipped creature gets +2/+1 and has haste.
Whenever a Warrior creature enters the battlefield, you may attach Obsidian Battle-Axe to it.
Equip {3}

Treasure Nabber

Whenever an opponent taps an artifact for mana, gain control of that artifact until the end of your next turn.

Wand of Wonder

{4}, {T}: Roll a d20. Each opponent exiles cards from the top of their library until they exile an instant or sorcery card, then shuffles the rest into their library. You may cast up to X instant and/or sorcery spells from among cards exiled this way without paying their mana costs.
1—9 | X is one.
10—19 | X is two.
20 | X is three.

Rose Room Treasurer

Alliance — Whenever another creature enters the battlefield under your control, create a Treasure token if this is the first or second time this ability has resolved this turn. Otherwise, you may pay {X}. When you do, Rose Room Treasurer deals X damage to any target.

Return the Favor

Spree (Choose one or more additional costs.)
+ {1} — Copy target instant spell, sorcery spell, activated ability, or triggered ability. You may choose new targets for the copy.
+ {1} — Change the target of target spell or ability with a single target.

Seething Song

Stormrider Rig

Equipped creature gets +1/+1.
Whenever a creature enters the battlefield under your control, you may attach Stormrider Rig to it.
Equip {2}

Impact Tremors

Whenever a creature enters the battlefield under your control, Impact Tremors deals 1 damage to each opponent.

Mana Geyser

Add {R} for each tapped land your opponents control.

Outpost Siege

As Outpost Siege enters the battlefield, 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.

Red Elemental Blast

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

Gimli of the Glittering Caves

Double strike
Whenever another legendary creature enters the battlefield under your control, put a +1/+1 counter on Gimli of the Glittering Caves.
Whenever Gimli deals combat damage to a player, create a Treasure token.

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.

Warstorm Surge

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

Wyll's Reversal

Choose target spell or ability with one or more targets. Roll a d20 and add the greatest power among creatures you control.
1—14 | You may choose new targets for that spell or ability.
15+ | You may choose new targets for that spell or ability. Then copy it. You may choose new targets for the copy.

Ronin Warclub

Equipped creature gets +2/+1.
Whenever a creature enters the battlefield under your control, attach Ronin Warclub to that creature.
Equip {5} ({5}: Attach to target creature you control. Equip only as a sorcery.)

Pandemonium

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

Sai of the Shinobi

Equipped creature gets +1/+1.
Whenever a creature enters the battlefield under your control, you may attach Sai of the Shinobi to it.
Equip {2}

Reverberate

Copy target instant or sorcery spell. You may choose new targets for the copy.

Kher Keep

{T}: Add {C}.
{1}{R}, {T}: Create a 0/1 red Kobold creature token named Kobolds of Kher Keep.

Tome of Legends

Tome of Legends enters the battlefield with a page counter on it.
Whenever your commander enters the battlefield or attacks, put a page counter on Tome of Legends.
{1}, {T}, Remove a page counter from Tome of Legends: Draw a card.

Norin the Wary

When a player casts a spell or a creature attacks, exile Norin the Wary. Return it to the battlefield under its owner's control at the beginning of the next end step.