Howl from Beyond

Target creature gets +X/+0 until end of turn.

Drain Life

Spend only black mana on X.
Drain Life deals X damage to any target. You gain life equal to the damage dealt, but not more life than the player's life total before the damage was dealt, the planeswalker's loyalty before the damage was dealt, or the creature's toughness.

Braingeyser

Power Sink

Counter target spell unless its controller pays {X}. If that player doesn't, they tap all lands with mana abilities they control and lose all unspent mana.

Badlands

Tropical Island

Taiga

Wild Growth

Enchant land
Whenever enchanted land is tapped for mana, its controller adds an additional {G}.

Savannah

Disintegrate

Disintegrate deals X damage to any target. If it's a creature, it can't be regenerated this turn, and if it would die this turn, exile it instead.

Guardian Angel

Prevent the next X damage that would be dealt to any target this turn. Until end of turn, you may pay {1} any time you could cast an instant. If you do, prevent the next 1 damage that would be dealt to that permanent or player this turn.

Sacrifice

As an additional cost to cast this spell, sacrifice a creature.
Add an amount of {B} equal to the sacrificed creature's mana value.

Shivan Dragon

Flying
{R}: This creature gets +1/+0 until end of turn.

Berserk

Cast this spell only before the combat damage step.
Target creature gains trample and gets +X/+0 until end of turn, where X is its power. At the beginning of the next end step, destroy that creature if it attacked this turn.

Forest

Serra Angel

Flying
Vigilance (Attacking doesn't cause this creature to tap.)

Swamp

Island

Birds of Paradise

Mountain

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Fireball

This spell costs {1} more to cast for each target beyond the first.
Fireball deals X damage divided evenly, rounded down, among any number of targets.