Alien Symbiosis

Enchant creature
Enchanted creature gets +1/+1, has menace, and is a Symbiote in addition to its other types.
You may cast this card from your graveyard by discarding a card in addition to paying its other costs.

Daily Bugle Building

{T}: Add {C}.
{1}, {T}: Add one mana of any color.
Smear Campaign — {1}, {T}: Target legendary creature gains menace until end of turn. Activate only as a sorcery.

Reanimate

Put target creature card from a graveyard onto the battlefield under your control. You lose life equal to its mana value.

Conjurer's Closet

At the beginning of your end step, you may exile target creature you control, then return that card to the battlefield under your control.

Gwenom, Remorseless

Deathtouch, lifelink
Whenever Gwenom attacks, until end of turn you may look at the top card of your library any time and you may play cards from the top of your library. If you cast a spell this way, pay life equal to its mana value rather than pay its mana cost.

Interdimensional Web Watch

When this artifact enters, exile the top two cards of your library. Until the end of your next turn, you may play those cards.
{T}: Add two mana in any combination of colors. Spend this mana only to cast spells from exile.

Carnage, Crimson Chaos

Trample
When Carnage enters, return target creature card with mana value 3 or less from your graveyard to the battlefield. It gains "This creature attacks each combat if able" and "When this creature deals combat damage to a player, sacrifice it."
Mayhem {B}{R}

Chainer, Nightmare Adept

Discard a card: You may cast a creature spell from your graveyard this turn. Activate only once each turn.
Whenever a nontoken creature you control enters, if you didn't cast it from your hand, it gains haste until your next turn.

Common Crook

When this creature dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Risky Research

Surveil 2, then draw two cards. You lose 2 life. (To surveil 2, look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Anger

Haste
As long as this card is in your graveyard and you control a Mountain, creatures you control have haste.

Behold the Sinister Six!

Return up to six target creature cards with different names from your graveyard to the battlefield.