Scurrilous Sentry

Menace
Whenever Scurrilous Sentry enters or attacks, it connives. (Draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on this creature.)

Waker of Waves

Creatures your opponents control get -1/-0.
{1}{U}, Discard Waker of Waves: Look at the top two cards of your library. Put one of them into your hand and the other into your graveyard.

Child of Night

Dimir Guildgate

Dimir Guildgate enters tapped.
{T}: Add {U} or {B}.

Raffine's Silencer

When Raffine's Silencer enters, it connives. (Draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on this creature.)
When Raffine's Silencer dies, target creature an opponent controls gets -X/-X until end of turn, where X is Raffine's Silencer's power.

Obsessive Stitcher

{T}: Draw a card, then discard a card.
{2}{U}{B}, {T}, Sacrifice Obsessive Stitcher: Return target creature card from your graveyard to the battlefield.

Island

Young Necromancer

When Young Necromancer enters, you may exile two cards from your graveyard. When you do, return target creature card from your graveyard to the battlefield.

Bonecaller Cleric

{3}{B}, Sacrifice Bonecaller Cleric: Return target creature card from your graveyard to the battlefield. Activate only as a sorcery.

Festering Mummy

When Festering Mummy dies, you may put a -1/-1 counter on target creature.

Goremand

As an additional cost to cast this spell, sacrifice a creature.
Flying
Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
When Goremand enters, each opponent sacrifices a creature.

Mire's Grasp

Enchant creature
Enchanted creature gets -3/-3.

Drekavac

When Drekavac enters, sacrifice it unless you discard a noncreature card.

Sphinx of Uthuun

Flying
When Sphinx of Uthuun enters, reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

Ransack the Lab

Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.

Swamp

Carrion Grub

Carrion Grub gets +X/+0, where X is the greatest power among creature cards in your graveyard.
When Carrion Grub enters, mill four cards. (Put the top four cards of your library into your graveyard.)

Zombify

Return target creature card from your graveyard to the battlefield.

Gloom Sower

Whenever Gloom Sower becomes blocked by a creature, that creature's controller loses 2 life and you gain 2 life.

Reave Soul

Destroy target creature with power 3 or less.

Discerning Taste

Look at the top four cards of your library. Put one of them into your hand and the rest into your graveyard. You gain life equal to the greatest power among creature cards put into your graveyard this way.

Hoverguard Sweepers

Flying
When Hoverguard Sweepers enters, you may return up to two target creatures to their owners' hands.

Spined Megalodon

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Whenever Spined Megalodon attacks, scry 1. (Look at the top card of your library. You may put that card on the bottom.)