Aurochs

Trample
Whenever Aurochs attacks, it gets +1/+0 until end of turn for each other attacking Aurochs.

Lead the Stampede

Look at the top five cards of your library. You may reveal any number of creature cards from among them and put the revealed cards into your hand. Put the rest on the bottom of your library in any order.

Forest

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Rugged Highlands

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {R} or {G}.

Woodland Changeling

Changeling (This card is every creature type.)

Mountain

Aurochs Herd

Trample
When Aurochs Herd enters, you may search your library for an Aurochs card, reveal it, put it into your hand, then shuffle.
Whenever Aurochs Herd attacks, it gets +1/+0 until end of turn for each other attacking Aurochs.

War-Spike Changeling

Changeling (This card is every creature type.)
{R}: War-Spike Changeling gains first strike until end of turn.

Llanowar Elves

Ranger's Guile

Target creature you control gets +1/+1 and gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Tanglesap

Prevent all combat damage that would be dealt this turn by creatures without trample.

Bull Aurochs

Trample
Whenever Bull Aurochs attacks, it gets +1/+0 until end of turn for each other attacking Aurochs.

Crown of Fury

Enchant creature
Enchanted creature gets +1/+0 and has first strike.
Sacrifice Crown of Fury: Enchanted creature and other creatures that share a creature type with it get +1/+0 and gain first strike until end of turn.