Event deck

An event deck is a type of Magic: The Gathering product that was sold as part of expert-level expansions starting with Mirrodin Besieged. From time to time giving up some of them, this product was officially discontinued after Battle for Zendikar.

Description
Unlike preconstructed theme decks and intro packs, which are constructed by Wizards of the Coast for newer players to Magic, event decks are built with more tournament-play competitive players in mind, and each event deck features seven to ten rares and as many as four copies of powerful common and uncommon cards.

Event decks are Standard legal as of their release and may be played fresh from their box, which contains a strategy insert with tips as to deck customization. The Modern Event Deck that was released in May 2014, is not set-specific and is for Modern rather than for Standard.

Original

 * a 60-card deck (seven rares and an indeterminable number of commons/uncommons).
 * a 15-card sideboard
 * a spindown life counter
 * a strategy guide
 * a box
 * a poster

From New Phyrexia forward

 * Eight rares

From Dragon's Maze forward

 * Only one event deck per release.
 * Ten rares

From Khans of Tarkir forward

 * Early 2014, it was announced that Event decks would alternate with the Clash pack. At the time this would mean that thay would appear in the first and third set for each block.

Battle for Zendikar

 * Eight rares, two mythics
 * After the change to two set blocks, Event decks were to be aligned with each first set, while Clash packs would appear with each second set.