As Tom Clancy's Rainbow Six Siege is breaching into video game stores nationwide, it's time we look back at the best of the best when it comes to strategic first-person shooting. Last year, we were saddened to learn that Tom Clancy's Rainbow 6: Patriots was cancelled. After Patriots' creative director, narrative director, lead designer and animation director were all removed from the project, we knew that Ubisoft would be pretty much remaking the game from the ground-up. As a result, the project was cancelled in mid-2014 and Siege was announced as the next Rainbow Six game.

The cancelled Patriots project was going to have the counter-terrorist unit Team Rainbow taking on a terrorist cell called the True Patriots, who were going to be causing all kinds of havoc throughout the boroughs of New York City. We're hoping some of those elaborate bridge shootout sequences we saw in its debut trailer have made it over into Siege. Nevertheless, it's time we remember one of the most unique first-person shooter franchises out there. In a scene dominated by the likes of Halo and Call of Duty, we're always glad to look back at a series that always tries to do something different. We decided not to include any of the series' expansions, as many of the PC Rainbow Six games had a slew of add-ons that you were able to get. Put your gas masks on and get ready to breach the door, because we're about to take down the Rainbow Six series, and we're going from Worst to First.