Tom Clancy's Rainbow Six Siege is an upcoming first-person shooter video game under development by Ubisoft Montreal and to be published by Ubisoft. It was announced by Ubisoft on June 9, 2014 at E3. The game uses Ubisoft's AnvilNext game engine. Considered as a successor to the now cancelled Tom Clancy's Rainbow 6: Patriots, Siege puts heavy emphasis on environmental destruction and co-operation between players. However, the title has no campaign and only offers an online mode.