I was recently introduced to a fun, if not all that balanced format called Horde Magic that was featured on Quiet Speculation recently. The format has a TON of potential and I wanted to share some of my thoughts with my readers.
First of all, I have written my own slight variation on the rules to make the game more balanced. We STEAMROLLED the Zombie Horde almost every time we played, and while it was still fun, a little more of a chance that the zombies will win would have increased the amount of fun that was had.
Secondly, the horde deck that we played against tended to have less-than-epic turns as far as the amount of zombie tokens that flipped each turn. It tended to only flip 1-2 cards, and those cards were not so much more powerful than a token that they made the zombies' board state increase in power to any significant degree.
Some tips for making a good Horde deck:
Make sure all non-token cards are SIGNIFICANTLY more powerful than the average token: [card]Rotting Fensnake[/card] didn't make the cut in my horde deck. I left those spaces open for things like [card]Gluttonous Zombie[/card] or [card]Tresserhorn Skyknight[/card].
Needs more card advantage/recursion/answers: When the opponent cannot make decisions, finding good answers is tough. [card]Fleshbag Marauder[/card] was in the sample Horde deck and makes the deck-without-a-pilot make a decision of which creature to sacrifice. I used cards like [card]Living Death[/card] and [card]Plague Wind[/card] to try and give the zombies more of an advantage. They effectively cannot do anything that is considered "the best" to do in magic. No card drawing, no "mana ramping"...[card]Ghoulraiser[/card] is an important addition, because it gives the Horde a little recursion without targeting/causing a decision. I also considered [card]Empty the Catacombs[/card] and may still add it at a later time.
You can see both the sample Horde deck and my horde deck on the Hoard Magic page here, don't get this format confused however with the Horde format from the Magic . People often name formats the same thing as others that haven't seen much play over the years and it makes cataloging them quite hard.