Spoiler

A spoiler is any information about an upcoming product prior to its release. In Magic, unlike many other media, spoilers are an expected part of the marketing for each new set.

Official spoilers become available through a planned preview season orchestrated by Wizards of the Coast. Occasionally, information about upcoming sets is leaked by outside parties instead. Wizards generally does not directly acknowledge leaks as a matter of policy. However, leaks have prompted statements regarding that policy and emphasizing the harm done by leaks.

Official reporting

During the preview season for an upcoming product, Wizards of the Coast publishes articles which include images of new cards, and which detail new mechanics, rules changes, and rulings that address expected difficulties. Prominent third parties are also given card images to preview, according to their audiences, on a schedule dictated by Wizards.

Unofficial reporting

Sites like MTGNews and MTG Salvation are known, loved, and hated for reporting on spoilers.

Leaks

Sources for unscheduled spoilers include early releases of magazines such as InQuest, The Duelist, Lotus Noir, Mana Rouge, and Scrye; websites outside of the United States, especially those in different time zones; foreign printings; art previews; panels at conventions; Ultra Pro products; official dealers; and digital leaks.

Noteworthy leaks

Invasion

In September 2000, an Invasion foil print sheet was auctioned on eBay weeks before the prerelease. The auction included a photo of the sheet, which included a then-new split card and provoked a lengthy discussion.

Judgment

On April 9, 2002, six weeks before the release of Judgment, the entirety of the set was accidentally made public through Magic Online, and publicized on MTGNews. This incident prompted a response from Wizards restating their policy of not commenting on leaks.

Time Spiral

In December 2005, Daron Rutter, under the name "rancored_elf", posted an image of three Time Spiral playtest cards on MTG Salvation, nine months before that set was released. This leak led to legal action against Rutter and ten John Doe defendants, which was settled out of court.

New Phyrexia

On April 20, 2011, the entirety of New Phyrexia was leaked when unauthorized players gained access to the set's "God Book". The "God Book", an item containing each card in the set, had been provided to Pro Tour player and journalist Guillaume Matignon for his use in writing for Lotus Noir. Matignon shared it with Guillaume Wafo-Tapa, after which it became available to the wider internet. Wizards then accelerated their normal preview schedule, providing official previews for the set over the course of a single week. Ultimately, four players, including both Matignon and Wafo-Tapa, received DCI suspensions for their part in the leaks, though Matignon's was later shortened.

Oath of the Gatewatch

On November 18, 2015, three cards from Oath of the Gatewatch were leaked. The leak provoked discussion of the new colorless mana symbol, , and spoiled the set's story by revealing Kozilek, the Great Distortion early. Further leaks for both Oath of the Gatewatch and its associated Zendikar Expeditions cards continued over the next month. These leaks led to a direct response from Wizards reiterating its frustration with the leaks. A subsequent investigation led to DCI suspensions for the members of a private Facebook group which was accused of participating in leaks over the course of multiple releases. As some of those players, notably including multiple judges, had not been actively engaged with the most recent leak, the administrator of the judging resource magicjudges.org briefly took down his site in protest. Less than a month later, Wizards retracted the suspensions of ten of the twelve players involved on appeal, and announced a new policy of explicitly stating the beginning of each spoiler season, to improve awareness of unofficial leaks.

Shadows over Innistrad

On February 6 and February 8, 2016, several cards from Shadows over Innistrad, including one complete booster pack, were leaked. The leak revealed most of the named mechanics in the set and included the set's checklist card, thus providing many card names and eliminating the possibility of several reprints. Flavor text and artwork indicate the involvement of Jace, Nahiri, Sorin, and Tamiyo in the story.

Eternal Masters

On February 15, 2016, the Twitter account "MTGDeepthroat" accused 2-3 unnamed vendors of possession of the card list for Eternal Masters and insider trading. Wizards issued a statement announcing an investigation into those accusations, and emphasized that they do not provide preferential treatment to any card vendor, distributor, or retailer; nor disclose detailed card set information prior to preview season. On February 17, MTGDeepthroat rescinded their original accusation, instead stating that the evidence for their original claim was fabricated, and promising to pursue legal action against its creator.