Tom Clancy’s Rainbow Six Siege is a first-person tactical shooter, in which players take control of an operator from the Rainbow team, a counter-terrorist unit. Different operators have different nationalities, perks, abilities and equipment. For instance, an operator named Twitch is equipped with a drone that can stun enemies with electric shock, while Smoke has the ability to detonate poison gases around, which can effectively lower the health of enemies in the affected areas. As a result, the game features an asymmetrical structure. Each side also gain access to a “Recruit”, whose gears and gadgets can be customized by players to meet the requirement of a match. Players can only play as one of the classes in a match, and cannot be switched throughout. Powerful weapons, like grenades and breach charges are valuable, as their number are limited under the system. Team-work is encouraged in Siege, and players are tasked to integrate their abilities to eliminate their enemies. Communications between players are also encouraged.