Skinbrand Goblin

Bloodrush — {R}, Discard Skinbrand Goblin: Target attacking creature gets +2/+1 until end of turn.

Scab-Clan Charger

Bloodrush — {1}{G}, Discard Scab-Clan Charger: Target attacking creature gets +2/+4 until end of turn.

Gruul Guildgate

This land enters tapped.
{T}: Add {R} or {G}.

Ranger's Path

Search your library for up to two Forest cards, put them onto the battlefield tapped, then shuffle.

Primal Huntbeast

Hexproof (This creature can't be the target of spells or abilities your opponents control.)

Rubblehulk

Rubblehulk's power and toughness are each equal to the number of lands you control.
Bloodrush — {1}{R}{G}, Discard Rubblehulk: Target attacking creature gets +X/+X until end of turn, where X is the number of lands you control.

Ground Assault

Ground Assault deals damage to target creature equal to the number of lands you control.

Predator's Rapport

Choose target creature you control. You gain life equal to that creature's power plus its toughness.

Alpha Authority

Enchant creature
Enchanted creature has hexproof and can't be blocked by more than one creature.

Fire Elemental

Pit Fight

Target creature you control fights another target creature. (Each deals damage equal to its power to the other.)

Gruul Keyrune

{T}: Add {R} or {G}.
{R}{G}: Gruul Keyrune becomes a 3/2 red and green Beast artifact creature with trample until end of turn.

Disciple of the Old Ways

{R}: Disciple of the Old Ways gains first strike until end of turn.

Arbor Elf

Mountain

Verdant Haven

Enchant land
When Verdant Haven enters, you gain 2 life.
Whenever enchanted land is tapped for mana, its controller adds an additional one mana of any color.

Foundry Street Denizen

Whenever another red creature you control enters, Foundry Street Denizen gets +1/+0 until end of turn.

Forest

Duskdale Wurm

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)

Gruul Ragebeast

Whenever Gruul Ragebeast or another creature you control enters, that creature fights target creature an opponent controls.

Slaughterhorn

Bloodrush — {G}, Discard Slaughterhorn: Target attacking creature gets +3/+2 until end of turn.

Ripscale Predator

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

Viashino Shanktail

First strike
Bloodrush — {2}{R}, Discard Viashino Shanktail: Target attacking creature gets +3/+1 and gains first strike until end of turn.

Ruination Wurm

Volcanic Geyser

Volcanic Geyser deals X damage to any target.

Ghor-Clan Rampager

Trample
Bloodrush — {R}{G}, Discard Ghor-Clan Rampager: Target attacking creature gets +4/+4 and gains trample until end of turn.

Skarrg Guildmage

{R}{G}: Creatures you control gain trample until end of turn.
{1}{R}{G}: Target land you control becomes a 4/4 Elemental creature until end of turn. It's still a land.

Centaur Courser

Zhur-Taa Swine

Bloodrush — {1}{R}{G}, Discard Zhur-Taa Swine: Target attacking creature gets +5/+4 until end of turn.