A co operative board game of global defense for 1 4 players based on the award winning video game xcom enemy unknown a free and innovative digital app coordinates the escalating alien invasion teaches you the game and serves as your rules reference players assume four distinct roles each of which is vital to xcom39s success commander chief scientist central of64258cer and squad leader a push your luck dice mechanic partners with the use of the app to heighten the game39s tension and drama