Act of Treason

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. (It can attack and {T} this turn.)

Mine Collapse

If it's your turn, you may sacrifice a Mountain rather than pay this spell's mana cost.
Mine Collapse deals 5 damage to target creature or planeswalker.

Horde Ambusher

Whenever Horde Ambusher blocks, it deals 1 damage to you.
Morph—Reveal a red card in your hand. (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When Horde Ambusher is turned face up, target creature can't block this turn.

Fractured Loyalty

Enchant creature
Whenever enchanted creature becomes the target of a spell or ability, that spell or ability's controller gains control of that creature. (This effect lasts indefinitely.)

Mountain

Traitorous Greed

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. Add two mana of any one color. (The creature can attack and {T} this turn.)

Smoldering Spires

Smoldering Spires enters tapped.
When Smoldering Spires enters, target creature can't block this turn.
{T}: Add {R}.

Wave of Indifference

X target creatures can't block this turn.

Unstable Hulk

Morph {3}{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.)
When Unstable Hulk is turned face up, it gets +6/+6 and gains trample until end of turn. You skip your next turn.

Incite

Target creature becomes red until end of turn and attacks this turn if able.

Skirk Marauder

Morph {2}{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.)
When Skirk Marauder is turned face up, it deals 2 damage to any target.

Panic Attack

Up to three target creatures can't block this turn.

Hijack

Gain control of target artifact or creature until end of turn. Untap it. It gains haste until end of turn.

Lust for War

Enchant creature
Whenever enchanted creature becomes tapped, Lust for War deals 3 damage to that creature's controller.
Enchanted creature attacks each combat if able.

Jeering Instigator

Morph {2}{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.)
When Jeering Instigator is turned face up, if it's your turn, gain control of another target creature until end of turn. Untap that creature. It gains haste until end of turn.