Free-for-All

When Free-for-All enters, exile all creatures face down.
At the beginning of each player's upkeep, that player chooses a card exiled with Free-for-All at random and puts it onto the battlefield.
When Free-for-All leaves the battlefield, put all cards exiled with it into their owners' graveyards.

The Big Top

{T}: Add one mana of any color that appears on your top. (A top is an outerwear garment worn on the upper body.)

Mouth to Mouth

Choose target opponent and target creature they control. You and that player have a breath-holding contest. If you win, you gain control of that creature.

Gifts Given

Search target opponent's library for four cards with different names and reveal them. That player chooses two of those cards. Put the chosen cards into the player's graveyard and the rest into your hand. Then that player shuffles their library.

Jack-in-the-Mox

{T}: Roll a six-sided die. This ability has the indicated effect.
1 — Sacrifice Jack-in-the-Mox and you lose 5 life.
2 — Add {W}.
3 — Add {U}.
4 — Add {B}.
5 — Add {R}.
6 — Add {G}.

Censorship

As Censorship enters, choose a word.
Whenever a player says the chosen word, Censorship deals 2 damage to that player.

Sorry

Before any player casts a spell with the same name as a card in any graveyard, that player may say "sorry." If they don't, any other player may say "sorry" as the spell is being cast. When another player says "sorry" this way, counter the spell.
Whenever a player says "sorry" at any other time, Sorry deals 2 damage to that player.

Question Elemental?

Did you know this creature has flying?
Are you aware that any time you say something that isn't a question, when a player points out this fact first, they gain control of Question Elemental?

Letter Bomb

When Letter Bomb enters, sign it and shuffle it into target player's library. That player reveals each card they draw until they draw Letter Bomb. When that player draws Letter Bomb, it deals 19½ damage to them.

Entirely Normal Armchair

During your turn, if Entirely Normal Armchair is in your hand, you may hide it on the battlefield.
{0}: Return Entirely Normal Armchair to its owner's hand. Only your opponents may activate this ability and only if they see Entirely Normal Armchair.
{2}, Sacrifice Entirely Normal Armchair: Destroy target attacking creature.

Hazmat Suit (Used)

Enchant creature
Enchanted creature gets +2/+1 and has menace.
Whenever a player's skin or fingernail touches enchanted creature, that player loses 2 life.

Clocknapper

When Clocknapper enters, choose beginning phase, first main phase, combat phase, postcombat main phase, or ending phase. Steal that phase from target player during their next turn. (That phase occurs as though it's your turn instead.)

Smart Ass

Whenever Smart Ass attacks, choose a card name. If defending player has no cards with the chosen name in their hand, they may reveal their hand. If they don't reveal their hand, Smart Ass can't be blocked this turn.

Kindslaver

{5}, {T}, Sacrifice Kindslaver: A person outside the game controls target player during that player's next turn. Neither player may advise that person until the end of that turn.

Hangman

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

Whenever a creature deals damage to a player, that player may say "Ow" once for each permanent named Ow. If the player doesn't, Ow deals 1 damage to them.

Cheatyface

If Cheatyface is in your hand, you may sneak Cheatyface onto the battlefield. If an opponent catches you right away, that player may exile Cheatyface.
Flying