The Pokémon TCG: EX Crystal Guardians expansion was released on August 30th, 2006.
EX Crystal Guardians
Come along for the exploration of EX Crystal Guardians, journeying further from the research village of Holon in search of new Pokémon Delta Species. Explorers and trainers have left the deep forest surrounding Holon, traveling across the water in pursuit of knowledge and new discoveries. What did they find on the beaches of the islands just off the coast?
Catch the Wave with... Water Pokémon?
Blastoise (2/100 & 9/100) shows up twice in this expansion—once as its standard Water-type that pours out damage with Hydro Pump, and a second time as a powerful Pokémon Delta Species. In its Fighting/Metal form, Blastoise mixes strong attacks with its Poké-Body Shield Veil, which removes the Weaknesses of your Pokémon. Ludicolo (6/100) is also a Pokémon Delta Species, but it goes in a different direction: as a Fire-type Pokémon powerhouse, especially when facing any Pokémon that has a Pokémon-ex as an ally!
Birds of a Feather, Rock Together
Fearow (18/100) and Pelipper (26/100) make Delta Species decks even stronger to play, adding several unique Poké-Powers to the mix. Fearow is a quick Stage 1 Pokémon to get started with—its Delta Sign Poké-Power allows you to search your deck for any kind of Pokémon Delta Species that you might need for free (even if it is just once each turn). Next, we cut Pelipper loose—its Delta Transport Poké-Power lets you switch 1 of your Active Pokémon that is a Delta Species with any of the Pokémon on your Bench. This kind of ability shows some powerful flexibility as a defense against Special Conditions and as an offensive maneuver to bring the right Pokémon up at the right time!
Crystals Clear, Get Them Here
The special crystals found on this island bring many strange and interesting abilities to your game. The first one, Cessation Crystal (74/100), offers an ability that most Trainers always look for when building a deck. Just attach this Pokémon Tool to one of your Active Pokémon, and neither player can use Poké-Powers or Poké-Bodies! Holon Circle (79/100) offers a different kind of control. This Stadium card shuts down the ability to attack... by anyone! It is not difficult to get rid of, but whoever wants to—you or your opponent—has to give up his or her attack to do it. Finally, the Pokémon Tool Mysterious Shard (81/100) offers a free round of protection from attacks by Pokémon-ex.
Everyone Loves Pokémon-ex
...unless you are playing against them! But if you have Sceptile ex (96/100) in play, it is not too bad—it stops Poké-Powers of Pokémon-ex, and makes it more expensive for all Pokémon-ex to attack. Jirachi ex (94/100) heads the other direction—its attacks becoming less costly to use if your opponent has powerful Pokémon in play. And finally, let us take a last look at the massive amount of Pokémon-ex in this expansion with Shiftry ex (97/100)... which damages your opponent’s Pokémon each time they use a Poké-Power. In all, players who explore EX Crystal Guardians are going to discover great new strategies to bring to their games!
Source:
https://www.pokemon.com/us/pokemon-tcg/ex-crystal-guardians