Mini mocks are essentially a half-scale version of a mock trial. They take about half the time, use about half the jurors and cost about half the money (sometimes even less). They are useful early in litigation to help get a read on the potential riskiness of a case and how preliminary case themes tend to play with jurors. They are especially helpful providing early feedback on cases with odd fact patterns or which contain some weird or atypical element.
Like a full mock trial, mini mocks are usually done in an adversarial format with thirty minute presentations each for plaintiff and defense. Following the presentations the single panel of surrogate jurors are either asked to briefly deliberate, or are led through a discussion by a facilitator. Mini mock trials are typically conducted in about four hours.