Pandemic is a cooperative board game designed by Matt Leacock and published by Z-Man Games in 2008. Pandemic is based on the premise that four diseases have broken out in the world, each threatening to wipe out a region. The game accommodates 2 to 4players, each playing one of five possible specialists: (dispatcher, medic, scientist, researcher or operations expert). The game is unlike most boardgames as the gameplay is cooperative, rather than competitive. Through the combined effort of all the players, the goal is to discover all four cures before any of several game-losing conditions are reached. An expansion, 'Pandemic: On the Brink' (co-designed by Matt Leacock and Tom Lehmann) adds several new roles and special events, and rules adjustments to allow a fifth player. In addition, several rules expansions are included, referred to as 'challenge kits'.