Strike It Rich

Create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Arc Runner

Haste (This creature can attack and {T} as soon as it comes under your control.)
At the beginning of the end step, sacrifice this creature.

Mountain

Animal Sanctuary

{T}: Add {C}.
{2}, {T}: Put a +1/+1 counter on target Bird, Cat, Dog, Goat, Ox, or Snake.

Ox of Agonas

When this creature enters, discard your hand, then draw three cards.
Escape—{R}{R}, Exile eight other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)
This creature escapes with a +1/+1 counter on it.

Bulwark Ox

Whenever this creature attacks while saddled, put a +1/+1 counter on target creature.
Sacrifice this creature: Creatures you control with counters on them gain hexproof and indestructible until end of turn.
Saddle 1 (Tap any number of other creatures you control with total power 1 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)

Talisman of Conviction

{T}: Add {C}.
{T}: Add {R} or {W}. This artifact deals 1 damage to you.

Elspeth's Smite

Elspeth's Smite deals 3 damage to target attacking or blocking creature. If that creature would die this turn, exile it instead.

Holy Cow

Flash
Flying
When this creature enters, you gain 2 life and scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Restless Bivouac

This land enters tapped.
{T}: Add {R} or {W}.
{1}{R}{W}: This land becomes a 2/2 red and white Ox creature until end of turn. It's still a land.
Whenever this land attacks, put a +1/+1 counter on target creature you control.

Plains

Dalkovan Packbeasts

Vigilance
Mobilize 3 (Whenever this creature attacks, create three tapped and attacking 1/1 red Warrior creature tokens. Sacrifice them at the beginning of the next end step.)

Bruse Tarl, Roving Rancher

Oxen you control have double strike.
Whenever Bruse Tarl enters or attacks, exile the top card of your library. If it's a land card, create a 2/2 white Ox creature token. Otherwise, you may cast it until the end of your next turn.

Purphoros's Emissary

Bestow {6}{R} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Menace (This creature can't be blocked except by two or more creatures.)
Enchanted creature gets +3/+3 and has menace.