'Villain' cards

At the beginning of combat on your turn, target noncreature artifact you control becomes an 8/8 Robot Villain artifact creature in addition to its other types.

Flying Whenever you discard a nonland card, put a +1/+1 counter on target Goblin you control. Whenever you discard a land card, create a tapped Treasure token.

Combined, enchanted, and equipped creatures you control have menace. {3}{B}{R}, {T}: Put two target creature cards from graveyards onto the battlefield combined into one creature under your control. (Its power is equal to their total power, its toughness is equal to their total toughness, and it has their names, mana costs, types, text boxes, etc.)

As this creature enters, secretly note a word with six to eight letters. {1}: Target player who doesn't control this creature guesses the noted word or an unguessed letter in that word. If they guess wrong, put a +1/+1 counter on this creature. Any player may activate this ability. When a player guesses the noted word or all of its letters, sacrifice this creature.

{1}{B/R}: Switch a Killbot or Mary O'Kill in your hand with one on the battlefield. (If a creature is tapped, the switched creature is tapped. The same is true for untapped, attacking, blocking, enchanted, equipped, and targeted. Any counters on a creature are on the switched creature instead.)

{2}{B/R}{B/R}, {T}: Roll a six-sided die. Create a number of 1/1 red Brainiac creature tokens equal to the result. Tap three untapped Brainiacs you control: The next time you would roll a six-sided die, instead roll two six-sided dice and use the total of those results.

Vigilance, menace {3}: Exile target creature card from a graveyard. When you do, put X +1/+1 counters on target Symbiote, where X is the exiled card's toughness.