This is the rules for Horde Magic from the main website here's the link
http://www.wizards.com/Magic/Magazine/Article.aspx?x=mtg/daily/sf/183In Brief: Horde Magic is a multiplayer variant where all players work together as "Survivors" to defeat an opposing "Horde" deck.
Rules Rundown: There's a lot going on in Horde Magic. We'll break it down into Game Play, Player, and Horde rules.
Game Play Rules:
•The objective is for the allied team to survive, and eliminate, the Horde. Survivors win when the Horde deck has no cards remaining in its library, no cards in hand, and controls no creatures.
•If the Survivors deal damage to the Horde, that number of cards are put from the top of the Horde's deck into its graveyard.
Player Rules:
•Up to four players total, and each player brings his or her own deck.
•All players share their turns, a la Two-Headed Giant, and contribute 20 life to the starting total (one player is 20, four players is 80).
•The Survivors takes the first three turns, then alternate with the Horde.
Horde Rules:
•The Horde is a hundred-card deck. (Take away a random twenty-five cards for each Survivor less than four on the team; three players face seventy-five cards, two players face fifty.)
•The Horde is both token cards as well as regular Magic cards; the standard is fifty-five 2/2 Zombie tokens, five 5/5 Zombie Giant tokens (from Zendikar), and forty assorted Zombies and other spells.
•The Horde's turns start by revealing the top card of the library. If it's a creature token, it is set aside. This process repeats until a nontoken spell is revealed. Then, all of the creature tokens are cast (as a Zombie creature spell that costs (0)). Finally, the revealed spell is cast.
•The Horde will only cast spells once per turn, at the start of the turn. (Anything that is returned to the Horde's hand remains there until the next turn, when it is then cast after the revealed spell for that turn.)
•The horde deck has any amount of mana needed and will always pay additional costs required (such as from Sphere of Resistance; Propaganda; and Kazuul, Tyrant of the Cliffs).
•All creatures the Horde controls have haste and must attack each turn if able.
•If there is a choice presented for the Horde, such as when a Survivor casts Fact or Fiction, the choice is made randomly.*
•Tokens put into the graveyard, returned to the Horde's hand, or exiled, disappear from the game as per normal token rules.
Decklist made by Adam Styborski
1 Abattoir Ghoul
1 Archdemon of Unx
4 Cackling Fiend
1 Death Baron
2 Diregraf Captain
1 Fleshbag Marauder
3 Geralf's Messenger
1 Gluttonous Zombie
1 Gravecrawler
2 Infectious Horror
1 Mikaeus, the Unhallowed
2 Nested Ghoul
4 Sightless Ghoul
1 Soulless One
2 Unbreathing Horde
1 Undead Warchief
1 Waning Wurm
5 Zombie Giant Token
55 Zombie Token
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89 creatures
1 Army of the Damned
1 Call to the Grave
2 Delirium Skeins
2 Endless Ranks of the Dead
1 Forsaken Wastes
1 Syphon Mind
1 Twilight's Call
1 Zombie Apocalypse
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10 other spells