The guild letter for the Izzet is also chuckle-worthy.
Welcome to the Izzet League, achievers of the impossible! Your work has led you to the guild that tries the untried, challenges the status quo, and defies such tedious concepts as "good enough" and "laboratory safety." Our mission is the venture unflinchingly into the unknown, with no concerns for the risks. Others may fear the volatility of our endeavors, but isn't ignorance the greatest danger of all? We understand that knowledge cannot be gained without passion, and that an explosion is the result.
In "The Secretist, Part 2", by Doug Beyer, Jace gets into a fight with Ruric-Thar. Unable to defeat a giant, two-headed, magic-resistant ogre with his usual arsenal of tricks and illusions, Jace throws the book out of the window and bites them in the kneepits. They are amused enough by this to concede and give him what he wants.
Kiora prefers the direct approach in acquiring assistance from her soon-to-be minions:
Cards are not popular just for their effects, brokenness, or artwork. Many cards find their ways into players' hearts because the Flavor Text accompanying the card ties everything together and is often hilarious.
During the launch party for Unglued (the joke set that makes fun of Magic itself), Mark Rosewater took the role of a judge... while wearing a chicken suit. He wore a donkey suit for the release of the sequel set, Unhinged. On a related note, Mark also made a list of his favorite funny quotes from the players at the Unglued launch party, found Here (at the end).
Anytime you and your friends play a game of Magic where Unglued or Unhinged is included. Anytime. Just an example:
(on turn 3) Friend 1:(stoic) For 3 mana, Farewell to Arms. Right hand. Go. Friend 2:(manages to go through his turn with his right hand behind his back) Go. Friend 1:(still stoic) For 3 mana, Farewell to Arms. Left hand. (smiles) Play with your feet, motherfucker.
At every opportunity, Wizards releases a "Mistform Ultimus Watch" that states every creature type the eponymous creature is. While it is amusing to have a creature that is, among other things, a Mutant, a Ninja, and a Turtle (No "Teenager" subtype yet), the funniest stuff comes from their snarky commentary on the matter.
Mistform Ultimus Watch, Theros edition: Obviously, becoming a God is sort of a big deal.
The ol' Chaos Confetti story. In a nutshell, a tourney player used the card Chaos Orb, which dictates that you toss the card into the air and anything it ends up touching when it lands gets destroyed. Instead, this guy tore it into pieces and sprinkled it onto the field, destroying pretty much everything his opponent had. This story eventually became an Ascended Meme with the creation of Chaos Confetti.
For bonus points, in one version of this legend, his opponent just called a judge who disqualified him for not having enough cards in deck.
This article, a parody of Mark Rosewater's work over the previous few months written by another staffer.
Maro: One morning, several years ago, I was sitting in my kitchen, eating a piping-hot bowl of cream of wheat. Evil Mark Rosewater: You live a life of danger! Maro: As I stared into this mushy glob of tastelessness, I became inspired. Maro: I asked myself, "Self, if cream of wheat was a Magic card, what would it look like?" Evil Mark Rosewater: And? Maro: Long story short, that's how Mercadian Masques came to be.
Persecute Artist. Longtime Magic artist Rebecca Guay is known for her beautiful, elegant watercolor illustrations for cards. At one point in time, she briefly came under fire from Magic's art director for how "girly" her card art was. The legions of Guay's fans were so unhappy, the event was immortalized in Unhinged.