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| Cosmic Eclipse Build & Battle Box
The Cosmic Eclipse Build & Battle Box is a special product given to participants at the start of Prerelease Tournaments for the Cosmic Eclipse expansion. These tournaments were held on the two weekends prior to the release of the expansion: October 19-20, and 26-27, 2019. The boxes were later made available to purchase at retail stores. Each box contains a random set of predetermined cards designed to enhance the experience of the Limited format events in which they were initially distributed.
Included in each Build & Battle Box 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 Cosmic Eclipse expansion are Buzzwole, Entei, Phione, and Blacephalon, with each containing a group of Pokémon cards that are focused around their following types respectively: Grass-type, Fire-type, Water-type, and Psychic-type.
The Cosmic Eclipse Build & Battle Boxes provided exclusive Non Holofoil versions of cards only available as Holofoil in Cosmic Eclipse booster packs: Sawsbuck, Dusknoir, and Rosa.
Each Build & Battle Box included two of the following four different groups of Pokémon cards, with one group always coinciding with the included Prerelease promo.
Each Build & Battle Box also included an additional random group of 4 of the following Supporter cards, with no more than 2 copies of a particular Supporter.