Generator Servant

{T}, Sacrifice this creature: Add {C}{C}. If that mana is spent on a creature spell, it gains haste until end of turn. (That creature can attack and {T} as soon as it comes under your control.)

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

Scuzzback Marauders

Trample
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Swamp

Magmaw

{1}, Sacrifice a nonland permanent: This creature deals 1 damage to any target.

Nightbird's Clutches

Up to two target creatures can't block this turn.
Flashback {3}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Bloodflow Connoisseur

Sacrifice a creature: Put a +1/+1 counter on this creature.

Olivia's Dragoon

Discard a card: This creature gains flying until end of turn.

Ghoulcaller's Accomplice

{3}{B}, Exile this card from your graveyard: Create a 2/2 black Zombie creature token. Activate only as a sorcery.

Double Cleave

Target creature gains double strike until end of turn. (It deals both first-strike and regular combat damage.)

Death Denied

Return X target creature cards from your graveyard to your hand.

Rakdos Shred-Freak

Golgari Thug

When this creature dies, put target creature card from your graveyard on top of your library.
Dredge 4 (If you would draw a card, you may mill four cards instead. If you do, return this card from your graveyard to your hand.)

Unholy Hunger

Destroy target creature.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, you gain 2 life.

Murderous Redcap

When this creature enters, it deals damage equal to its power to any target.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Appetite for Brains

Target opponent reveals their hand. You choose a card from it with mana value 4 or greater and exile that card.

Malevolent Whispers

Gain control of target creature until end of turn. Untap that creature. It gets +2/+0 and gains haste until end of turn.
Madness {3}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Ghoulsteed

{2}{B}, Discard two cards: Return this card from your graveyard to the battlefield tapped.

Heap Doll

Sacrifice this creature: Exile target card from a graveyard.

Ulamog's Crusher

Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents of their choice.)
This creature attacks each combat if able.

Gurmag Angler

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)

Last Gasp

Target creature gets -3/-3 until end of turn.

Akroan Crusader

Heroic — Whenever you cast a spell that targets this creature, create a 1/1 red Soldier creature token with haste. (It can attack and {T} as soon as it comes under your control.)

Shriekmaw

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
When this creature enters, destroy target nonartifact, nonblack creature.
Evoke {1}{B} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Fume Spitter

Sacrifice this creature: Put a -1/-1 counter on target creature.

Soul's Fire

Target creature you control deals damage equal to its power to any target.

Arena Athlete

Heroic — Whenever you cast a spell that targets this creature, target creature an opponent controls can't block this turn.

Seize the Day

Untap target creature. After this main phase, there is an additional combat phase followed by an additional main phase.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Molten Birth

Create two 1/1 red Elemental creature tokens, then flip a coin. If you win the flip, return Molten Birth to its owner's hand.

Mountain

Cathodion

Slum Reaper

When this creature enters, each player sacrifices a creature of their choice.

Beckon Apparition

Exile target card from a graveyard. Create a 1/1 white and black Spirit creature token with flying.