Opportunistic Dragon

Flying
When Opportunistic Dragon enters, choose target Human or artifact an opponent controls. For as long as Opportunistic Dragon remains on the battlefield, gain control of that permanent, it loses all abilities, and it can't attack or block.

Syr Carah, the Bold

Whenever Syr Carah, the Bold or an instant or sorcery spell you control deals damage to a player, exile the top card of your library. You may play that card this turn.
{T}: Syr Carah deals 1 damage to any target.

Ogre Errant

Whenever Ogre Errant attacks, another target attacking Knight gains menace until end of turn. (It can't be blocked except by two or more creatures.)

Skullknocker Ogre

Whenever Skullknocker Ogre deals damage to an opponent, that player discards a card at random. If the player does, they draw a card.

Embereth Skyblazer

During your turn, Embereth Skyblazer has flying.
Whenever Embereth Skyblazer attacks, you may pay {2}{R}. If you do, creatures you control get +X/+0 until end of turn, where X is the number of opponents you have.

Thrill of Possibility

As an additional cost to cast this spell, discard a card.
Draw two cards.

Raging Redcap

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.

Battle Display

Destroy target artifact. (Then exile this card. You may cast the creature later from exile.)

Embereth Shieldbreaker

Embereth Shieldbreaker // Battle Display

Scorching Dragonfire

Scorching Dragonfire deals 3 damage to target creature or planeswalker. If that creature or planeswalker would die this turn, exile it instead.

Embercleave

Flash
This spell costs {1} less to cast for each attacking creature you control.
When Embercleave enters, attach it to target creature you control.
Equipped creature gets +1/+1 and has double strike and trample.
Equip {3}

Rowan, Fearless Sparkmage

+1: Up to one target creature gets +3/+0 and gains first strike until end of turn.
−2: Rowan, Fearless Sparkmage deals 1 damage to each of up to two target creatures. Those creatures can't block this turn.
−9: Gain control of all creatures until end of turn. Untap them. They gain haste until end of turn.

Haggle

You may discard a card. If you do, draw a card. (Then exile this card. You may cast the creature later from exile.)

Merchant of the Vale

Merchant of the Vale // Haggle

Robber of the Rich

Reach, haste
Whenever Robber of the Rich attacks, if defending player has more cards in hand than you, exile the top card of their library. During any turn you attacked with a Rogue, you may cast that card and you may spend mana as though it were mana of any color to cast that spell.

Joust

Choose target creature you control and target creature you don't control. The creature you control gets +2/+1 until end of turn if it's a Knight. Then those creatures fight each other. (Each deals damage equal to its power to the other.)

Mountain

Barge In

Target attacking creature gets +2/+2 until end of turn. Each attacking non-Human creature gains trample until end of turn.

Dwarven Mine

({T}: Add {R}.)
Dwarven Mine enters tapped unless you control three or more other Mountains.
When Dwarven Mine enters untapped, create a 1/1 red Dwarf creature token.

Sundering Stroke

Sundering Stroke deals 7 damage divided as you choose among one, two, or three targets. If at least seven red mana was spent to cast this spell, instead Sundering Stroke deals 7 damage to each of those permanents and/or players.

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.

Brimstone Trebuchet

Defender, reach
{T}: Brimstone Trebuchet deals 1 damage to each opponent.
Whenever a Knight you control enters, untap Brimstone Trebuchet.

Embereth Paladin

Haste
Adamant — If at least three red mana was spent to cast this spell, Embereth Paladin enters with a +1/+1 counter on it.

Rowan's Stalwarts

When Rowan's Stalwarts enters, you may search your library and/or graveyard for a card named Rowan, Fearless Sparkmage, reveal it, and put it into your hand. If you search your library this way, shuffle.

Seven Dwarves

Seven Dwarves gets +1/+1 for each other creature named Seven Dwarves you control.
A deck can have up to seven cards named Seven Dwarves.

Boulder Rush

Target creature gets +2/+0 until end of turn. (Then exile this card. You may cast the creature later from exile.)

Rimrock Knight

Rimrock Knight // Boulder Rush

Blow Your House Down

Up to three target creatures can't block this turn. Destroy any of them that are Walls.

Searing Barrage

Searing Barrage deals 5 damage to target creature.
Adamant — If at least three red mana was spent to cast this spell, Searing Barrage deals 3 damage to that creature's controller.

Heraldic Banner

As Heraldic Banner enters, choose a color.
Creatures you control of the chosen color get +1/+0.
{T}: Add one mana of the chosen color.

Slaying Fire

Slaying Fire deals 3 damage to any target.
Adamant — If at least three red mana was spent to cast this spell, it deals 4 damage instead.

Crystal Slipper

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

Weaselback Redcap

{1}{R}: Weaselback Redcap gets +2/+0 until end of turn.

Stomp

Damage can't be prevented this turn. Stomp deals 2 damage to any target.

Bonecrusher Giant

Whenever Bonecrusher Giant becomes the target of a spell, Bonecrusher Giant deals 2 damage to that spell's controller.

Bonecrusher Giant // Stomp

Tome of Legends

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

Castle Embereth

Castle Embereth enters tapped unless you control a Mountain.
{T}: Add {R}.
{1}{R}{R}, {T}: Creatures you control get +1/+0 until end of turn.