Otherworldly Gaze

Surveil 3. (Look at the top three cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
Flashback {1}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

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.

Void Mirror

Whenever a player casts a spell, if no colored mana was spent to cast it, counter that spell.

Narcomoeba

Flying
When this card is put into your graveyard from your library, you may put it onto the battlefield.

Polluted Delta

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

Overgrown Tomb

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

Surgical Extraction

({B/P} can be paid with either {B} or 2 life.)
Choose target card in a graveyard other than a basic land card. Search its owner's graveyard, hand, and library for any number of cards with the same name as that card and exile them. Then that player shuffles.

Swamp

Stitcher's Supplier

When this creature enters or dies, mill three cards. (Put the top three cards of your library into your graveyard.)

Spell Pierce

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

Prized Amalgam

Whenever a creature enters, if it entered from your graveyard or you cast it from your graveyard, return this card from your graveyard to the battlefield tapped at the beginning of the next end step.

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.

Gravecrawler

This creature can't block.
You may cast this card from your graveyard as long as you control a Zombie.

Abrupt Decay

This spell can't be countered.
Destroy target nonland permanent with mana value 3 or less.

Creeping Chill

Creeping Chill deals 3 damage to each opponent and you gain 3 life.
When Creeping Chill is put into your graveyard from your library, you may exile it. If you do, Creeping Chill deals 3 damage to each opponent and you gain 3 life.

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.

Wonder

Flying
As long as this card is in your graveyard and you control an Island, creatures you control have flying.

Watery Grave

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

Haunted Dead

When this creature enters, create a 1/1 white Spirit creature token with flying.
{1}{B}, Discard two cards: Return this card from your graveyard to the battlefield tapped.

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.)

Glimpse the Unthinkable

Venture Deeper

Target player mills four cards. (Then exile this card. You may cast the creature later from exile.)

Merfolk Secretkeeper

Merfolk Secretkeeper // Venture Deeper

Breeding Pool

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