Flying Octobot

Flying
Whenever another Villain you control enters, put a +1/+1 counter on this creature. This ability triggers only once each turn.

Unstable Experiment

Target player draws a card, then up to one 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.)

Mysterio, Master of Illusion

When Mysterio enters, create a 3/3 blue Illusion Villain creature token for each nontoken Villain you control. Exile those tokens when Mysterio leaves the battlefield.

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.

Spider-Byte, Web Warden

When Spider-Byte enters, return up to one target nonland permanent to its owner's hand.

Tombstone, Career Criminal

When Tombstone enters, return target Villain card from your graveyard to your hand.
Villain spells you cast cost {1} less to cast.

Swamp

Chameleon, Master of Disguise

You may have Chameleon enter as a copy of a creature you control, except his name is Chameleon, Master of Disguise.
Mayhem {2}{U} (You may cast this card from your graveyard for {2}{U} if you discarded it this turn. Timing rules still apply.)

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.)

Pumpkin Bombardment

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

Morbius the Living Vampire

Flying, vigilance, lifelink
{U}{B}, Exile this card from your graveyard: Look at the top three cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Doc Ock, Sinister Scientist

As long as there are eight or more cards in your graveyard, Doc Ock has base power and toughness 8/8.
As long as you control another Villain, Doc Ock has hexproof. (He can't be the target of spells or abilities your opponents control.)

Robotics Mastery

Flash
Enchant creature
When this Aura enters, create two 1/1 colorless Robot artifact creature tokens with flying.
Enchanted creature gets +2/+2.

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.)

Mysterio's Phantasm

Flying, vigilance
Whenever this creature attacks, mill a card. (Put the top card of your library into your graveyard.)

Venom's Hunger

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

Island

Morlun, Devourer of Spiders

Lifelink
Morlun enters with X+1/+1 counters on him.
When Morlun enters, he deals X damage to target opponent.

Mob Lookout

When this creature enters, 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.)

Scorpion's Sting

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

Prowler, Clawed Thief

Menace (This creature can't be blocked except by two or more creatures.)
Whenever another Villain you control enters, Prowler connives. (Draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on this creature.)

Black Cat, Cunning Thief

When Black Cat enters, look at the top nine cards of target opponent's library, exile two of them face down, then put the rest on the bottom of their library in a random order. You may play the exiled cards for as long as they remain exiled. Mana of any type can be spent to cast spells this way.

The Spot's Portal

Put target creature on the bottom of its owner's library. You lose 2 life unless you control a Villain.

Sinister Hideout

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

Whoosh!

Kicker {1}{U} (You may pay an additional {1}{U} as you cast this spell.)
Return target nonland permanent to its owner's hand. If this spell was kicked, draw a card.