Shriek, Treblemaker

At the beginning of your first main phase, you may discard a card. When you do, target creature can't block this turn.
Sonic Blast — Whenever a creature an opponent controls dies, Shriek deals 1 damage to that player.

Spider-Man Noir

Menace
Whenever a creature you control attacks alone, put a +1/+1 counter on it. Then surveil X, where X is the number of counters on it. (Look at the top X cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Venom's Hunger

This spell costs {2} less to cast if you control a Villain.
Destroy target creature. You gain 2 life.

Prison Break

Return target creature card from your graveyard to the battlefield with an additional +1/+1 counter on it.
Mayhem {3}{B} (You may cast this card from your graveyard for {3}{B} if you discarded it this turn. Timing rules still apply.)

Mechanical Mobster

When this creature enters, exile up to one target card from a graveyard. Target creature you control connives. (Draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on that creature.)

Taxi Driver

{1}, {T}: Target creature gains haste until end of turn.

Spider-Islanders

Mayhem {1}{R} (You may cast this card from your graveyard for {1}{R} if you discarded it this turn. Timing rules still apply.)

Ominous Asylum

This land enters tapped.
{T}: Add {B} or {R}.
{4}, {T}: Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Hobgoblin, Mantled Marauder

Flying, haste
Whenever you discard a card, Hobgoblin gets +2/+0 until end of turn.

Swarm, Being of Bees

Flash
Flying
Mayhem {B} (You may cast this card from your graveyard for {B} if you discarded it this turn. Timing rules still apply.)

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.")

Mountain

Shock

Swamp

Romantic Rendezvous

Scarlet Spider, Kaine

Menace (This creature can't be blocked except by two or more creatures.)
When Scarlet Spider enters, you may discard a card. If you do, put a +1/+1 counter on him.
Mayhem {B/R} (You may cast this card from your graveyard for {B/R} if you discarded it this turn. Timing rules still apply.)

Merciless Enforcers

Lifelink
{3}{B}: This creature deals 1 damage to each opponent.

Wisecrack

Target creature deals damage equal to its power to itself. If that creature is attacking, Wisecrack deals 2 damage to that creature's controller.

Shocker, Unshakable

During your turn, Shocker has first strike.
Vibro-Shock Gauntlets — When Shocker enters, he deals 2 damage to target creature and 2 damage to that creature's controller.

Inner Demons Gangsters

Discard a card: This creature gets +1/+0 and gains menace until end of turn. Activate only as a sorcery. (It can't be blocked except by two or more creatures.)

Pumpkin Bombardment

As an additional cost to cast this spell, discard a card or pay {2}.
Pumpkin Bombardment deals 3 damage to target creature.

Stegron the Dinosaur Man

Menace (This creature can't be blocked except by two or more creatures.)
Dinosaur Formula — {1}{R}, Discard this card: Until end of turn, target creature you control gets +3/+1 and becomes a Dinosaur in addition to its other types.

Scorpion's Sting

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

Electro's Bolt

Electro's Bolt deals 4 damage to target creature.
Mayhem {1}{R} (You may cast this card from your graveyard for {1}{R} if you discarded it this turn. Timing rules still apply.)