During the years of playtesting and development, a large portion of our games were played multiplier, and most of those were Team-Ups. We just love a good two-on-two. The game plays marvelously well that way, and without requiring a special board or extra space.
Official rules for multiplayer, including 2 vs 2, will be coming out with Mage Wars Battlegrounds, slated for later this year. We are working on spells specifically designed to help your partner and hinder another team.
Please share any thoughts you might have! :-)