From the publisher's website:

Adventure Awaits! Living in the walls Lurk things that aren't nice, That nobody knows of Except for the mice. In Mice & Mystics players take on the roles of those still loyal to the king - but to escape the clutches of Vanestra, they have been turned into mice! Play as cunning field mice who must race through a castle now twenty times larger than before. The castle would be a dangerous place with Vanestra's minions in control, but now countless other terrors also await heroes who are but the size of figs. Play as nimble Prince Colin and fence your way past your foes, or try Nez Bellows, the burly smith. Confound your foes as the wizened old mouse Maginos, or protect your companions as Tilda, the castle's former healer. Every player will have a vital role in the quest to warn the king, and it will take careful planning to find Vanestra's weakness and defeat her. Mice & Mystics is a cooperative adventure game in which the players work together to save an imperiled kingdom. They will face countless adversaries such as rats, cockroaches, and spiders, and of course the greatest of all horrors: the castle's housecat, Brodie. Mice & Mystics is a boldly innovative game that thrusts players into an ever-changing, interactive environment, and features a rich storyline that the players help create as they play the game. The Cheese System allows players to hoard the crumbs of precious cheese they find on their journey, and use it to bolster their mice with grandiose new abilities and overcome seemingly insurmountable odds. Mice & Mystics will provide any group of friends with an unforgettable adventure they will be talking about for years to come. Assuming they can all squeak by... Throughout the long ages One lesson is well-learned, Nothing's half as dang'rous As a sorceress spurned.