<Li> Situations: the game's most significant single - player component, with 10 solo and 1 coop multiplayer missions that serve as introductory and interactive tutorials to the game's mechanics . </Li> <Li> Outbreak: A limited time event exclusive to Operation Chimera, Outbreak pits a 3 player team in a co-op PVE environment against an alien biohazard threat, namely AI - controlled heavily mutated forms of humans infected with said alien parasite . Two difficulties exists for this mode, for which the chief difference was the inclusion of friendly fire on the harder one . </Li> <P> Three years after the Rainbow Program's deactivation, there is a resurgence of terrorist activities, with the White Mask being the most prominent . The terrorists' goals are unknown, yet they are causing chaos across the world . To counter this rising threat, the program is reactivated by a new leader who is simply known as Six (voiced by Angela Bassett). Six assembles a group of special forces operatives from different countries to face and combat the White Masks . Recruits go through multiple exercises to prepare them for future encounters with the White Masks, training to perform hostage rescue and bomb disposal . Eventually, the White Masks launch a chemical attack on a university (called Bartlett University), and the recruits are sent to disarm the bombs and eliminate the enemy presence . The operation is a massive success, though there are casualties . The story ends with Six affirming that the reactivation of Team Rainbow is the best and only choice in a time filled with risks and uncertainties . Team Rainbow is ready for their next mission--to hunt down the leader of their enemy--and they stand prepared to protect and defend their nation from terrorists . </P> <P> This entire project was born and has grown out of an in - depth study that looked to distill what the Rainbow series is at its core in terms of both fantasy and gameplay . At the end of the day, the Rainbow Six fantasy about being part of the greatest counter-terrorist organization and impersonating the best of the best operators, working as a team, (and) carrying out dangerous operations (hostage rescue) anywhere on the globe </P>

What is the story behind rainbow six siege
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