The names of the Theme Decks are references to the Japanese name of the set.
EX Unseen Forces is the first set since Neo Destiny to contain Unown. In the English set, the Unown have their own sub-set and numbering system, each one numbered as @/28. While they were either common or uncommon in the Japanese set, they were all holographic in the English version. An Unown replaced the reverse-holographic card in every fifth pack.
The second “o” in Ho-Oh is capitalized in this set, unlike in previous sets where it was written in lowercase.
The reverse-holographic design for this set features a 3D Poké Ball pattern and the EX Unseen Forces set logo.
This is the last set to have an Owner's Pokémon ex.
The secret box topper for this set is Rocket's Persian ex. Another secret card, Celebi ex, appeared randomly in booster packs.
The Prerelease card for this set is Bayleef. In the United States, Prereleases were held on the weekends of 13th/14th, 20th/21st and 27th/28th August 2005. An unusual third weekend was added as the second weekend clashed with Worlds 2005.
The symbol for EX Unseen Forces is Ho-Oh's left wing crossing over Lugia's right wing.
The Japanese Half Decks for this set were the Generation II Starter Pokémon, but the Epic Collection Decks were nearly the exact same, just in English instead of Japanese.