Unstable contains 216-ish cards (5 basic land, TBA common, TBA uncommon, TBA rare, and TBA mythic rare) and includes randomly inserted premium versions of all cards. The set explores new areas of Magic game design and continues the tradition of bending the conventional rules of the game in a fun and whimsical way. Silver-bordered cards can do interesting and unique things that regular black-bordered cards don’t typically get to do, all in the name of fun, and the set’s creative elements reflect that spirit. Unstable was designed to both be drafted alone and be mixed with other sets. According to Mark Rosewater however, the best experience is probably when it’s drafted alone. The expansion symbol is a a wrench with an acorn shaped hole.
The set features ‘modern design sensibilities’ and a is built around a ‘cohesive creative vision’. It includes fun Legendary creatures that can be utilized in the Commander format and some cards designed for cubes. Like its predecessors, Unstable features 5 full-art basic lands, but these are borderless instead of black-bordered. Almost every pack contains one of these lands. Very infrequently, it is replaced by a Steamflogger Boss. The set further features foil tokens (both for tokens produced by cards in the set and for popular tribes outside the set).