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Here's a summary of the news:
Zant (Twilight Princess), Midna (Twilight Princess), and Ghirahim (Skyward Sword) are confirmed to be playable characters. Lana, a sorceress, has been introduced as a character unique to Hyrule Warriors. She fights using a book of sorcery and is described as a "key character to the story."
Chain Chomp, who originated from the Mario universe, will appear in Hyrule Warriors as a weapon.
Hyrule Warriors will include a badge crafting system, which can help to increase a characters statistics. Crafting uses items which are dropped by enemies.
Adventure Mode will be available. It will be set up like the classic 8-bit Zelda top-down style map. Each square that the player steps into initiates a challenge to be played out in the combat style of Hyrule Warriors. For example, kill five million enemies in 30 seconds. As each grid is completed new grids open, allowing players to unlock new weapons, items, and characters. It described as "a bit similar to classic Zelda games."
Gold Skulltulas are back for players to collect.
To close off the presentation, Ganandorf has been revealed as a playable character. Preorder bonuses are also shown, which include costumes for select characters. No mention of whether these will be available outside of North America.
Source: GameSpot
