Cavalier of Flame

{1}{R}: Creatures you control get +1/+0 and gain haste until end of turn.
When Cavalier of Flame enters, discard any number of cards, then draw that many cards.
When Cavalier of Flame dies, it deals X damage to each opponent and each planeswalker they control, where X is the number of land cards in your graveyard.

Chandra's Ignition

Target creature you control deals damage equal to its power to each other creature and each opponent.

Valakut, the Molten Pinnacle

Valakut, the Molten Pinnacle enters tapped.
Whenever a Mountain you control enters, if you control at least five other Mountains, you may have Valakut, the Molten Pinnacle deal 3 damage to any target.
{T}: Add {R}.

Countryside Crusher

At the beginning of your upkeep, reveal the top card of your library. If it's a land card, put it into your graveyard and repeat this process.
Whenever a land card is put into your graveyard from anywhere, put a +1/+1 counter on Countryside Crusher.

High Market

{T}: Add {C}.
{T}, Sacrifice a creature: You gain 1 life.

Mountain

Augusta, Dean of Order

Other tapped creatures you control get +1/+0.
Other untapped creatures you control get +0/+1.
Whenever you attack, untap each creature you control, then tap any number of creatures you control.

Plargg, Dean of Chaos

{T}, Discard a card: Draw a card.
{4}{R}, {T}: Reveal cards from the top of your library until you reveal a nonlegendary, nonland card with mana value 3 or less. You may cast that card without paying its mana cost. Put all revealed cards not cast this way on the bottom of your library in a random order.