Dragon Mantle

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

Iroas's Blessing

Enchant creature you control
When Iroas's Blessing enters, it deals 4 damage to target creature or planeswalker an opponent controls.
Enchanted creature gets +1/+1.

Hero of the Games

Whenever you cast a spell that targets Hero of the Games, creatures you control get +1/+0 until end of turn.

Goblin War Paint

Enchant creature
Enchanted creature gets +2/+2 and has haste.

Gingerbrute

Haste (This creature can attack and {T} as soon as it comes under your control.)
{1}: Gingerbrute can't be blocked this turn except by creatures with haste.
{2}, {T}, Sacrifice Gingerbrute: You gain 3 life.

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

Mountain

Nef-Crop Entangler

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
You may exert Nef-Crop Entangler as it attacks. When you do, it gets +1/+2 until end of turn. (An exerted creature won't untap during your next untap step.)

Heroes of the Revel

When Heroes of the Revel enters, create a 1/1 red Satyr creature token with "This creature can't block."
Whenever you cast a spell that targets Heroes of the Revel, creatures you control get +1/+0 until end of turn.

Boggart Brute

Menace (This creature can't be blocked except by two or more creatures.)

Akroan Crusader

Heroic — Whenever you cast a spell that targets Akroan Crusader, create a 1/1 red Soldier creature token with haste. (It can attack and {T} as soon as it comes under your control.)

Valduk, Keeper of the Flame

At the beginning of combat on your turn, for each Aura and Equipment attached to Valduk, Keeper of the Flame, create a 3/1 red Elemental creature token with trample and haste. Exile those tokens at the beginning of the next end step.

Cartouche of Zeal

Enchant creature you control
When Cartouche of Zeal enters, target creature can't block this turn.
Enchanted creature gets +1/+1 and has haste. (It can attack and {T} no matter when it came under your control.)

Thriving Bluff

Thriving Bluff enters tapped. As it enters, choose a color other than red.
{T}: Add {R} or one mana of the chosen color.