Thanks to MattWang97 for live tweeting the panel, we are able to report the following details about Scars of Mirrodin. This information is coming from a panel held by R&D members at the San Diego Comic-Con. According to Matt, the hall was completely packed seating approximately 200. Also on location was @parrakum, who posted excellent pictures to his blog at GiftsUngiven.com

Sword of Body and Mind

Mythic

Artifact - Equipment

Equipped creature gets +2/+2 and has protection from green and from blue.

Whenever equipped creature deals combat damage to a player, you put a 2/2 green wolf token onto the battlefield and that player puts the top 10 cards of his or her library into his or her graveyard.

Equip

@MattWang97

New Elspeth - They confirmed that Scars of Mirrodin will feature the next iteration of Elspeth (however it will be Elspeth 1.0 in the Duels decks)

New Planeswalker: Koth - There will be a new planeswalker named Koth in Scars of Mirrodin. He is fighting alongside Elspeth in the art shown, and according to Matt he was shirtless with braided hair. A comment Rosewater made hints that he might be mono-colored. (Originally we were told the name was Kost.)

Old Mirrodin Mechanic - There are four possibilities: Equipment, Imprint, Entwine and Affinity. We can ignore the first and last. Equipment because it's commonplace now, and Affinity because it has been an eternal battle to keep it from. Entwine is the most exciting and likely given the powerful access players have to mana, casting costs are no longer prohibitive. It is possible that the mechanic might be from the Mirrodin BLOCK so that would enable Dark Steel and Fifth Dawn as well. We'll see in the coming months.

Zombies and Vampires - Despite the loss of Nocturnus, Vampires will continue as a supported tribe. Zombies will also be present in Scars of Mirrodin.

Here are a few of the pictures taken by @parrakum:

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