Mountain

Empty the Warrens

Create two 1/1 red Goblin creature tokens.
Storm (When you cast this spell, copy it for each spell cast before it this turn.)

Bitter Reunion

When Bitter Reunion enters the battlefield, you may discard a card. If you do, draw two cards.
{1}, Sacrifice Bitter Reunion: Creatures you control gain haste until end of turn.

Burning-Tree Emissary

When Burning-Tree Emissary enters the battlefield, add {R}{G}.

Llanowar Elves

Copperline Gorge

Copperline Gorge enters the battlefield tapped unless you control two or fewer other lands.
{T}: Add {R} or {G}.

Domri, Anarch of Bolas

Creatures you control get +1/+0.
+1: Add {R} or {G}. Creature spells you cast this turn can't be countered.
−2: Target creature you control fights target creature you don't control.

Chromatic Star

{1}, {T}, Sacrifice Chromatic Star: Add one mana of any color.
When Chromatic Star is put into a graveyard from the battlefield, draw a card.

Karplusan Forest

{T}: Add {C}.
{T}: Add {R} or {G}. Karplusan Forest deals 1 damage to you.

Pyretic Ritual

Desperate Ritual

Add {R}{R}{R}.
Splice onto Arcane {1}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Aeve, Progenitor Ooze

Storm (When you cast this spell, copy it for each spell cast before it this turn. Copies become tokens.)
Aeve, Progenitor Ooze isn't legendary if it's a token.
Aeve enters the battlefield with a +1/+1 counter on it for each other Ooze you control.

Game Trail

As Game Trail enters the battlefield, you may reveal a Mountain or Forest card from your hand. If you don't, Game Trail enters the battlefield tapped.
{T}: Add {R} or {G}.

Forest

Manamorphose

Add two mana in any combination of colors.
Draw a card.

Seasonal Ritual

Add one mana of any color. (Then exile this card. You may cast the creature later from exile.)