The Countdown Is at One

Players play a Magic subgame, starting at 1 life and using their libraries as their decks. For the rest of the main game, if a source would deal damage to a player who didn't win the subgame, it deals double that damage to that player instead.

Ignacio of Myra's Marvels

As Ignacio of Myra's Marvels enters, choose armor, blood, book, bottle, fang, fire, scroll, spear, sword, or water.
Whenever you cast a spell with the chosen object in its art, create two Treasure tokens.
Partner (You can have two commanders if both have partner.)

Oddly Uneven

Choose one —
• Destroy each creature with an odd number of words in its name. (Hyphenated words are one word.)
• Destroy each creature with an even number of words in its name.

Clay Pigeon

Flying
{1}, Throw Clay Pigeon into the air at least two feet above your head while seated: If you catch Clay Pigeon with one hand, prevent all damage a source of your choice would deal to you this turn and tap Clay Pigeon. Otherwise, sacrifice it.

Sex Appeal

Prevent the next 3 damage that would be dealt this turn to any number of targets, divided as you choose. If there are more people in the room of a different gender than you are as you cast this spell, prevent the next 6 damage this way instead.

Rings of Brighthearth

Whenever you activate an ability, if it isn't a mana ability, you may pay {2}. If you do, copy that ability. You may choose new targets for the copy.

Toy Boat

Cumulative upkeep—Say "Toy Boat" quickly. (At the beginning of your upkeep, put an age counter on Toy Boat, then sacrifice it unless you say "Toy Boat" once for each age counter on it—without pausing between or fumbling it.)

Mirror Mirror

Mirror Mirror enters tapped.
{7}, {T}, Sacrifice Mirror Mirror: Choose target player. At the beginning of the next end step, exchange life totals with that player, exchange control of all permanents you and that player control, and exchange cards in your hands, cards in your libraries, and cards in your graveyards.

Head to Head

You and target opponent play Seven Questions with the top card of that player's library. If you win, prevent all damage that would be dealt this turn by a source of your choice. (To play Seven Questions, that player looks at the card, then you ask up to six yes-or-no questions about the card that they answer truthfully. You guess the card's name—that's question seven—then the player reveals the card.)

Giant Fan

{2}, {T}: Move a counter from one permanent onto another. If the second permanent refers to any kind of counter, the moved counter becomes one of those counters. Otherwise, it becomes a +1/+1 counter.

Mana Screw

{1}: Flip a coin. If you win the flip, add {C}{C}. Activate only as an instant.

Jalum Grifter

{1}{R}, {T}: Shuffle Jalum Grifter and two lands you control face down. Target opponent chooses one of those cards. Turn the cards face up. If they chose Jalum Grifter, sacrifice it. Otherwise, destroy target permanent.

Gimme Five

You gain 1 life for each person who high-fives you in the next thirty seconds. Each player in an Un-game who high-fives you gains 1 life. (Offer high fives. Don't hit people.)

Have

Plains

Ancient Den

Chaos Confetti

{4}, {T}: Tear Chaos Confetti into pieces. Throw the pieces onto the battlefield from a distance of at least five feet. Destroy each permanent that a piece touches. Remove the pieces from the game.

Mountain

Old Guard

{W}, {T}: Tap target creature without reminder text. (Reminder text is still any italicized text in parentheses that explains rules you already know.)

Boomstacker

As Boomstacker enters and whenever it attacks, stack two dice on top of it. (All dice must be stacked vertically, one on top of another.)
Boomstacker gets +1/+1 for each die in its stack.
Boomstacker attacks each combat if able.
When the stack falls, sacrifice Boomstacker.

Flavor Judge

{T}: Choose target spell or ability that targets a permanent you control. Then ask a person outside the game if the story of what will happen makes sense. If they say no, sacrifice Flavor Judge and counter that spell or ability.

Do-It-Yourself Seraph

Flying
Whenever Do-It-Yourself Seraph attacks, you may search your library for an artifact card, exile it, then shuffle.
Do-It-Yourself Seraph has the text box of each card exiled with Do-It-Yourself Seraph in addition to its own.

The Ultimate Nightmare of Wizards of the Coast® Customer Service

The Ultimate Nightmare of Wizards of the Coast® Customer Service deals X damage to each of Y target creatures and Z target players or planeswalkers.

Gobsmacked

Enchant nonland permanent
As Gobsmacked enters, choose a person outside the game.
As long as you can see the chosen person from your seat, enchanted permanent can't attack or block, and its activated abilities can't be activated.

AWOL

Exile target attacking creature. Then remove it from the game. Then put it into the absolutely-removed-from-the-freaking-game-forever zone.

World-Bottling Kit

{5}, Sacrifice World-Bottling Kit: Choose a Magic set. Exile all permanents with that set's expansion symbol except for basic lands.

Rules Lawyer

State-based actions don't apply to you or other permanents you control. (You don't lose the game due to having 0 or less life or drawing from an empty library. Your creatures aren't destroyed due to damage or deathtouch and aren't put into a graveyard due to having 0 or less toughness. Your planeswalkers aren't put into a graveyard if they have 0 loyalty. You don't put a legendary permanent into a graveyard if you control two with the same name. Counters aren't removed from your permanents due to game rules. Permanents you control attached or combined illegally remain on the battlefield. For complete rules and regulations, see rule 704.)

Assembled Ensemble

Vigilance
Assembled Ensemble's power is equal to the number of Robots you control.
Whenever you cast a spell with an artifact creature in its art, create a 1/1 white Clown Robot artifact creature token.

Osgir, the Reconstructor

Vigilance
{1}, Sacrifice an artifact: Target creature you control gets +2/+0 until end of turn.
{X}, {T}, Exile an artifact card with mana value X from your graveyard: Create two tokens that are copies of the exiled card. Activate only as a sorcery.

Blue Ribbon

When Blue Ribbon enters, ask a person outside the game which creature you control is most deserving of a blue ribbon. Attach Blue Ribbon to that creature.
Equipped creature has best in show. (Whenever another creature becomes the target of a spell or ability you control, you may copy that spell or ability. If you do, the copy targets this creature.)
Equip {3}

Sacrifice Play

A person outside the game chooses an attacking or blocking creature target opponent controls. That player sacrifices that creature.

Pointy Finger of Doom

{3}, {T}: Spin Pointy Finger of Doom in the middle of the table so that it rotates completely at least once, then destroy the closest permanent the finger points to.

Modular Monstrosity

Whenever an opponent casts a spell, you have five seconds to choose a keyword you haven't chosen for a card named Modular Monstrosity today that's been printed on a creature card. If you do, Modular Monstrosity gains that ability. Otherwise, Modular Monstrosity loses all keyword abilities.

Split Screen

When Split Screen enters, shuffle your library and deal it into four libraries. If anything refers to your library, choose one of your libraries for it.
Play with your libraries' top cards revealed.
When Split Screen leaves the battlefield, shuffle your libraries together.

City of Ass

City of Ass enters tapped.
{T}: Add one and one-half mana of any one color.

Sol Ring

Carnival Barker

{T}: You have thirty seconds to laud a creature you control to any people outside the game. Until end of turn, that creature gains trample and haste and gets +X/+0, where X is the number of those people who applauded. Activate only as a sorcery and only once.

Bronze Calendar

Spells you cast cost {1} less to cast.
You must speak in a voice other than your normal voice.
When you speak in your normal voice, sacrifice Bronze Calendar.

Goblin S.W.A.T. Team

Say "Goblin S.W.A.T. Team": Put a +1/+1 counter on Goblin S.W.A.T. Team unless an opponent swats the table within five seconds. Activate only once each turn.

Rod of Spanking

{2}, {T}: Rod of Spanking deals 1 damage to target player. Then untap Rod of Spanking unless that player says "Thank you, sir. May I have another?"

Park Map

{1}, Sacrifice Park Map: Search your library for a land card that doesn't have the same art as a permanent you control, reveal it, put it into your hand, then shuffle.

Form of the Approach of the Second Sun

When this enchantment enters, you gain 7 life. You become a card until you leave your library or that library is shuffled. Put yourself seventh from the top, balancing the cards on top of you on your head.
When you draw yourself, you win the game.
When one or more cards fall off your head, exile them and all cards on your head, then sacrifice this enchantment.

Everythingamajig

{1}: Flip a coin. If you win the flip, add {C}{C}. Activate only as an instant.
{3}, {T}: Target player discards a card. Activate only during your turn.
{X}: Everythingamajig becomes an X/X Construct artifact creature until end of turn.

Time Machine

{T}: Exile Time Machine and target nontoken creature you own. Return them to the battlefield at the beginning of your upkeep on your turn X in the next game you play with one of your opponents in this game, where X is the mana value of the exiled creature.

First Come, First Served

Each attacking or blocking creature with the lowest collector number among attacking or blocking creatures has first strike.

Urza's Contact Lenses

Urza's Contact Lenses enters tapped.
Urza's Contact Lenses doesn't untap during your untap step.
As long as Urza's Contact Lenses is untapped, all players play with their hands revealed.
Clap your hands twice: You may tap or untap Urza's Contact Lenses.

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.

Man of Measure

As long as you're shorter than an opponent, Man of Measure gets +0/+1 and has first strike.
As long as you're taller than an opponent, Man of Measure gets +1/+0.

Buzzing Whack-a-Doodle

As Buzzing Whack-a-Doodle enters, you and an opponent each secretly choose Whack or Doodle. Then those choices are revealed. If the choices match, Buzzing Whack-a-Doodle has that ability. Otherwise, it has Buzz.
• Whack — {T}: Target player loses 2 life.
• Doodle — {T}: You gain 3 life.
• Buzz — {2}, {T}: Draw a card.

Devil K. Nevil

Haste
When Devil K. Nevil enters, jump it over any number of creatures. If it clears those creatures, put that many +1/+1 counters on it. (You can see a jumping demonstration at DevilKNevil.com.)

My First Tome

{1}, {T}: Say the flavor text on a card in your hand. Target opponent guesses that card's name. You may reveal that card. If you do and they guessed wrong, you draw a card.

Infinity Elemental

Gleemax

You choose all targets for all spells and abilities.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Darksteel Citadel

Blacker Lotus

{T}: Tear Blacker Lotus into pieces. Add four mana of any one color. Remove the pieces from the game.

Charm School

As Charm School enters, choose a color and balance Charm School on your head.
Prevent all damage that would be dealt to you by sources of the chosen color.
When Charm School falls off your head, sacrifice Charm School.

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.

Staff of the Letter Magus

As Staff of the Letter Magus enters, choose a consonant other than N, R, S, or T.
Whenever a player casts a spell, you gain 1 life for each time the chosen letter appears in that spell's name.

Battlemage's Bracers

Equipped creature has haste.
Whenever an ability of equipped creature is activated, if it isn't a mana ability, you may pay {1}. If you do, copy that ability. You may choose new targets for the copy.
Equip {2}

Frankie Peanuts

At the beginning of your upkeep, you may ask target player a yes-or-no question. If you do, that player answers the question truthfully and abides by that answer if able until end of turn.

R&D's Secret Lair

Play cards as written. Ignore all errata.
{T}: Add {C}. (This mana is still added to your mana pool.)

Frazzled Editor

Protection from wordy (Something is wordy if it has four or more lines of rules text.)

Get Your Head in the Game

Flash
When Get Your Head in the Game enters, exile target nonland permanent until it (this card) leaves the battlefield, then touch it (this card) to your head. When it (this card) stops touching it (your head), sacrifice it (the card, not your head).

Jackknight

Whenever another artifact you control enters, put a +1/+1 counter on Jackknight. If that artifact is a Contraption, Jackknight gains lifelink until end of turn.

Impounding Lot-Bot

When Impounding Lot-Bot enters, you may say "INCARCERATE!" in a robot voice. If you do, exile another target artifact or enchantment until Impounding Lot-Bot leaves the battlefield.

Ashnod's Coupon

{T}, Sacrifice Ashnod's Coupon: Target player gets you target drink. You pay any costs for the drink.

Battlefield Forge

{T}: Add {C}.
{T}: Add {R} or {W}. Battlefield Forge deals 1 damage to you.

Emcee

Whenever another creature enters, you may stand up and say in a deep, booming voice, "Presenting . . . " and that creature's name. If you do, put a +1/+1 counter on that creature.

Knight of the Hokey Pokey

First strike
{1}{W}, Do the Hokey Pokey: Prevent all damage a source of your choice would deal to Knight of the Hokey Pokey this turn. (To do the Hokey Pokey, choose an arm, a leg, or your whole self and put it in. Put it out. Put it in. Shake it all about. You do the Hokey Pokey! Turn yourself around.)