Renegade Doppelganger

Whenever another creature you control enters, you may have this creature become a copy of that creature until end of turn. (If it does, it loses this ability for the rest of the turn.)

Creeping Tar Pit

This land enters tapped.
{T}: Add {U} or {B}.
{1}{U}{B}: This land becomes a 3/2 blue and black Elemental creature until end of turn and can't be blocked this turn. It's still a land.

Island

Ornithopter

Hedron Crab

Landfall — Whenever a land you control enters, target player mills three cards. (They put the top three cards of their library into their graveyard.)

Birds of Paradise

Darkslick Shores

This land enters tapped unless you control two or fewer other lands.
{T}: Add {U} or {B}.

Necrotic Ooze

As long as this creature is on the battlefield, it has all activated abilities of all creature cards in all graveyards.

Bonehoard

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +X/+X, where X is the number of creature cards in all graveyards.
Equip {2}

Verdant Catacombs

{T}, Pay 1 life, Sacrifice this land: Search your library for a Swamp or Forest card, put it onto the battlefield, then shuffle.

Lotus Cobra

Landfall — Whenever a land you control enters, add one mana of any color.

Swamp

Sylvan Ranger

When this creature enters, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Enclave Cryptologist

Level up {1}{U} ({1}{U}: Put a level counter on this. Level up only as a sorcery.)
LEVEL 1-2
0/1
{T}: Draw a card, then discard a card.
LEVEL 3+
0/1
{T}: Draw a card.

Forest

Scalding Tarn

{T}, Pay 1 life, Sacrifice this land: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

Fauna Shaman

{G}, {T}, Discard a creature card: Search your library for a creature card, reveal it, put it into your hand, then shuffle.

Gigantomancer

{1}: Target creature you control has base power and toughness 7/7 until end of turn.

Misty Rainforest

{T}, Pay 1 life, Sacrifice this land: Search your library for a Forest or Island card, put it onto the battlefield, then shuffle.

Vengevine

Haste
Whenever you cast a spell, if it's the second creature spell you cast this turn, you may return this card from your graveyard to the battlefield.

Molten-Tail Masticore

At the beginning of your upkeep, sacrifice this creature unless you discard a card.
{4}, Exile a creature card from your graveyard: This creature deals 4 damage to any target.
{2}: Regenerate this creature.