Run Amok

Target attacking creature gets +3/+3 and gains trample until end of turn.

Stomping Ground

({T}: Add {R} or {G}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Mountain

Lightning Strike

Lightning Strike deals 3 damage to any target.

Rescue

Return target permanent you control to its owner's hand.

Enigma Drake

Flying
Enigma Drake's power is equal to the number of instant and sorcery cards in your graveyard.

Enter the Unknown

Target creature you control explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on the creature, then put the card back or put it into your graveyard.)
You may play an additional land this turn.

Siren Stormtamer

Flying
{U}, Sacrifice this creature: Counter target spell or ability that targets you or a creature you control.

Titanic Brawl

This spell costs {1} less to cast if it targets a creature you control with a +1/+1 counter on it.
Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

Negate

Deeproot Champion

Whenever you cast a noncreature spell, put a +1/+1 counter on this creature.

Forest

Chart a Course

Draw two cards. Then discard a card unless you attacked this turn.

Merfolk Trickster

Flash
When this creature enters, tap target creature an opponent controls. It loses all abilities until end of turn.

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Dive Down

Target creature you control gets +0/+3 and gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Shivan Fire

Kicker {4} (You may pay an additional {4} as you cast this spell.)
Shivan Fire deals 2 damage to target creature. If this spell was kicked, it deals 4 damage instead.

Breeding Pool

({T}: Add {G} or {U}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Thud

As an additional cost to cast this spell, sacrifice a creature.
Thud deals damage equal to the sacrificed creature's power to any target.

Steam Vents

({T}: Add {U} or {R}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Island

Pelt Collector

Whenever another creature you control enters or dies, if that creature's power is greater than this creature's, put a +1/+1 counter on this creature.
As long as this creature has three or more +1/+1 counters on it, it has trample.

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Pteramander

Flying
{7}{U}: Adapt 4. This ability costs {1} less to activate for each instant and sorcery card in your graveyard. (If this creature has no +1/+1 counters on it, put four +1/+1 counters on it.)