Timmy, Power Gamer

{4}: You may put a creature card from your hand onto the battlefield.

Infinity Elemental

Enter the Dungeon

Players play a Magic subgame under the table, starting at 5 life and using their libraries as their decks. The winner searches their library for two cards, puts those cards into their hand, then shuffles.

Spike, Tournament Grinder

({B/P} can be paid with either {B} or 2 life.)
{B/P}{B/P}{B/P}{B/P}: Reveal a card you own from outside the game that has been banned or restricted in a Constructed format and put it into your hand.

Ghoulcaller's Chant

Choose one —
• Return target creature card from your graveyard to your hand.
• Return two target Zombie cards from your graveyard to your hand.

Johnny, Combo Player

{4}: Search your library for a card, put that card into your hand, then shuffle.

Super-Duper Death Ray

Trample (This spell can deal excess damage to its target's controller.)
Super-Duper Death Ray deals 4 damage to target creature.

Staying Power

"Until end of turn" and "this turn" effects don't end.

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

Sword of Dungeons & Dragons

Equipped creature gets +2/+2 and has protection from Rogues and from Clerics.
Whenever equipped creature deals combat damage to a player, create a 4/4 gold Dragon creature token with flying and roll a d20 (a twenty-sided die). If you roll a 20, repeat this process.
Equip {2}

Clocknapper

When this creature 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.)

Earl of Squirrel

Squirrellink (Damage dealt by this creature also causes you to create that many 1/1 green Squirrel creature tokens.)
Creature tokens you control are Squirrels in addition to their other creature types.
Other Squirrels you control get +1/+1.

Jack-in-the-Mox

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

Better Than One

A person outside the game becomes your teammate. (Choose any number of cards in your hand, on top of your library, or on the battlefield under your control. Those cards become your teammate's hand, library, and permanents, respectively.)

Very Cryptic Command

Choose two —
• Counter target black-bordered spell.
• Return target creature to its owner's hand.
• Untap each permanent you control with a watermark.
• Roll two six-sided dice. Target player mills X cards, where X is the total of those results.

The Grand Calcutron

When The Grand Calcutron enters, each player's hand becomes a program (an ordered row of revealed cards).
Players can play only the first card of their program.
If a card would be put into a player's hand from anywhere, that player reveals it and places it anywhere within their program instead.
At the beginning of each player's end step, if that player's program has fewer than five cards, they draw cards equal to the difference.
The Grand Calcutron can be your commander.

Phoebe, Head of S.N.E.A.K.

Phoebe can't be blocked by creatures with flavor text.
{2}{U}{B}: Phoebe permanently steals target creature's text box. (That creature loses all rules text, flavor text, and watermarks. This creature gains them.)

Yet Another Aether Vortex

All creatures have haste.
Players play with the top card of their libraries revealed.
Noninstant, nonsorcery cards on top of a library are on the battlefield under their owner's control in addition to being in that library.

Creature Guy

Gotcha — If an opponent says "creature" or "guy," you may say "Gotcha!" When you do, return Creature Guy from your graveyard to your hand.

Slaying Mantis

Just a second (As long as this spell is on the stack, players can't move permanents.)
This creature enters by being thrown from a distance of at least three feet.
When this creature enters, it fights each creature an opponent controls that it touched as it entered.

Dr. Julius Jumblemorph

Dr. Julius Jumblemorph is every creature type (even if this card isn't on the battlefield).
Whenever a host you control enters, you may search your library and/or graveyard for a card with augment and combine it with that host. If you search your library this way, shuffle.

Strategy, Schmategy

Roll a six-sided die. Strategy, Schmategy has the indicated effect.
1 — Do nothing.
2 — Destroy all artifacts.
3 — Destroy all lands.
4 — Strategy, Schmategy deals 3 damage to each creature and each player.
5 — Each player discards their hand and draws seven cards.
6 — Repeat this process two more times.

Topsy Turvy

The phases of each player's turn are reversed. (The phases are, in reverse order, ending, second main, combat, first main, and beginning.)
As long as there are more than two players in the game, the turn order is reversed.

The Cheese Stands Alone

When you control no permanents other than The Cheese Stands Alone and have no cards in hand, you win the game.

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.)

Magical Hacker

{U}: Change the text of target spell or permanent by replacing all instances of + with -, and vice versa, until end of turn.

Ordinary Pony

When this creature enters, you may exile target non-Horse creature you control that wasn't put onto the battlefield with this ability this turn, then return it to the battlefield under its owner's control.

Mox Lotus

{T}: Add {∞}.
{100}: Add one mana of any color.

Mirror Mirror

This artifact enters tapped.
{7}, {T}, Sacrifice this artifact: 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.

Symbol Status

Create a 1/1 colorless Expansion-Symbol creature token for each different expansion symbol among permanents you control.

Incoming!

Each player searches their library for any number of artifact, creature, enchantment, and/or land cards, puts them onto the battlefield, then shuffles.

Sly Spy

Whenever this creature deals combat damage to a player, that player reveals the top card of their library. Put that card into your hand and you lose life equal to its mana value.

Old-Fashioned Vampire

Flying
This creature gets +2/+2 and has deathtouch as long as it's dark outdoors.

Baron Von Count

Baron Von Count enters with a doom counter on "5."
Whenever you cast a spell with the indicated numeral in its mana cost, text box, power, or toughness, move the doom counter one numeral to the left.
When the doom counter moves from "1," destroy target player and put that doom counter on "5."

Ashnod's Coupon

{T}, Sacrifice this artifact: Target player gets you target drink. You pay any costs for the drink.