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| Steam Siege Prerelease Kit
The Steam Siege Prerelease Kit is a special product given to participants at the start of Prerelease Tournaments for the Steam Siege expansion. Prerelease Tournaments for the Steam Siege expansion were held on the two weekends prior to the release of the expansion, on July 23-24, and 30-31, 2016. Each Kit contains a random set of predetermined cards designed to enhance the experience of the Limited format tournament that follows.
Included in each Prerelease Kit is a 23-card Evolution pack that includes one of four specially stamped Prerelease cards for the expansion, as well as four booster packs. The Prerelease cards for the Steam Siege expansion are Yanmega, Volcanion, Clawitzer, and Hoopa, with the four different groups of possible Pokémon cards being based on their four types: Grass-type, Fire-type, Water-type, and Psychic-type.
Evolution Prerelease Kit structure
Each Prerelease Kit included two of the following four different groups of Pokémon cards, with one group always coinciding with the included Prerelease promo.
Each Prerelease Kit also included an additional random group of predetermined Trainer cards. As the Yanmega Group and Volcanion Group have 1 less card compared to the other two groups, a Kit will contain 6-8 Trainer Cards (excluding the Level Ball provided by the Hoopa Group) depending on which two groups the Kit contains. A Kit should find 3-4 in any combination of the Supporter cards and 3-4 in any combination of Item cards were included (but no more than 2 copies of a particular Trainer card).