| Release date
|| September 30, 2005 (Early release)|
October 7, 2005 (General release)
The Holon Research Tower Water Quarter Deck (Japanese: ホロンの研究塔ハーフデッキ1/2水EX Holon Research Tower Half Deck 1/2 Water EX) is a Japanese-exclusive Quarter Deck (see Half Deck) that complements the Holon Research Tower expansion of the Pokémon Trading Card Game.
The majority of these cards could not be found in the main expansion. Those that were not were added to the main set when the English version was made.
Like other Half Decks, the Holon Research Tower Water Quarter Deck also includes a rulebook, damage counters, and status counters.