Guttersnipe

Whenever you cast an instant or sorcery spell, Guttersnipe deals 2 damage to each opponent.

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

Titan's Strength

Target creature gets +3/+1 until end of turn. Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Lightning Strike

Lightning Strike deals 3 damage to any target.

Mountain

Bellows Lizard

{1}{R}: Bellows Lizard gets +1/+0 until end of turn.

Minotaur Skullcleaver

Haste
When Minotaur Skullcleaver enters the battlefield, it gets +2/+0 until end of turn.

Dragon Mantle

Enchant creature
When Dragon Mantle enters the battlefield, draw a card.
Enchanted creature has "{R}: This creature gets +1/+0 until end of turn."

Chandra, Torch of Defiance

+1: Exile the top card of your library. You may cast that card. If you don't, Chandra, Torch of Defiance deals 2 damage to each opponent.
+1: Add {R}{R}.
−3: Chandra, Torch of Defiance deals 4 damage to target creature.
−7: You get an emblem with "Whenever you cast a spell, this emblem deals 5 damage to any target."

Shock

Racecourse Fury

Enchant land
Enchanted land has "{T}: Target creature gains haste until end of turn."

Dynacharge

Target creature you control gets +2/+0 until end of turn.
Overload {2}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Messenger's Speed

Enchant creature
Enchanted creature has trample and haste.

Fanatic of Mogis

When Fanatic of Mogis enters the battlefield, 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.)

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.