The official Pokémon website has posted the two new LEGEND cards which feature Ho-oh and Lugia. Each Pokémon LEGEND requires two special cards to create one larger completed card. To play a Pokémon LEGEND, you must have both halves of the Pokémon in your hand and you must play them at the same time.

Below is part of the news that was posted on the official site regarding these new cards and the rule changes regarding them.

Pokémon LEGENDs are unique in that, when in play, they are neither Basic Pokémon nor Evolved Pokémon. As such, they can't be played during the set-up phase at the beginning of the game (only Basic Pokémon can be played then). But they also can't be hit by attacks that target Basic Pokémon or Evolved Pokémon specifically. Pokémon LEGENDs are like no Pokémon you’ve ever seen before!


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As mentioned, one of the new Pokémon LEGENDs is Ho-Oh LEGEND. With its enormous fiery wings stretching over the two cards, the extraordinary Ho-Oh LEGEND is truly awe-inspiring. As the first of its kind, Ho-Oh LEGEND lives up to its name: a 140HP difference maker that can find a home in virtually any deck. With the Sacred Rainbow Poké-Body, all of the Energy attached to Ho-Oh LEGEND becomes Fire Energy, making Ho-Oh LEGEND usable now matter what kinds of Energy you have in your deck. Ho-Oh LEGEND can pound the Defending Pokémon with the Bright Wing attack, delivering 100 damage. The attack requires 4 Fire Energy (and you must discard one Energy attached to Ho-Oh LEGEND when you attack); fortunately, with the Sacred Rainbow Poké-Body, it won’t matter what kind of Energy is attached!

Source: http://www.pokemon.com/us/news/tcg_hgss1_ho-oh-2010-01-12/