Brinebarrow Intruder

Flash
When this creature enters, target creature an opponent controls gets -2/-0 until end of turn.

Slither Blade

Rouse

If you control a Swamp, you may pay 2 life rather than pay this spell's mana cost.
Target creature gets +2/+0 until end of turn.

Island

Relic's Roar

Until end of turn, target artifact or creature becomes a Dinosaur artifact creature with base power and toughness 4/3 in addition to its other types.

Brine Shaman

{T}, Sacrifice a creature: Target creature gets +2/+2 until end of turn.
{1}{U}{U}, Sacrifice a creature: Counter target creature spell.

Illvoi Galeblade

Flash
Flying
{2}, Sacrifice this creature: Draw a card.

Unstable Mutation

Enchant creature
Enchanted creature gets +3/+3.
At the beginning of the upkeep of enchanted creature's controller, put a -1/-1 counter on that creature.

Demonic Appetite

Enchant creature you control
Enchanted creature gets +3/+3.
At the beginning of your upkeep, sacrifice a creature.

Humbling Elder

Village Rites

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Tormented Soul

This creature can't block and can't be blocked.

Behind the Mask

As an additional cost to cast this spell, you may collect evidence 6. (Exile cards with total mana value 6 or greater from your graveyard.)
Until end of turn, target artifact or creature becomes an artifact creature with base power and toughness 4/3. If evidence was collected, it has base power and toughness 1/1 until end of turn instead.

Disrupt

Counter target instant or sorcery spell unless its controller pays {1}.
Draw a card.

Swamp

Vampire's Bite

Kicker {2}{B} (You may pay an additional {2}{B} as you cast this spell.)
Target creature gets +3/+0 until end of turn. If this spell was kicked, that creature gains lifelink until end of turn. (Damage dealt by the creature also causes its controller to gain that much life.)

Nested Shambler

When this creature dies, create X tapped 1/1 green Squirrel creature tokens, where X is this creature's power.