Today during Ubisoft's E3 press conference, the publisher officially confirmed that the long-in-development squad-based first-person shooter Rainbow Six Patriots has been rebooted as the Counter-Strike-esque Rainbow Six Siege.

According to Rainbow Six brand director Alexander Remy and creative director for Xavier Marquis, no remnants of Patriots remain in Siege;. Developer Ubisoft Montreal started from scratch--with a new team of developers behind it--about 18 months ago

Siege will launch across Xbox One, PlayStation 4, and PC in 2015. The game is not coming to Xbox 360 or PlayStation 3. A 5v5 squad-based shooter, Rainbow Six Siege will feature close-quarter indoor battles that pit counter-terrorism squads against enemies.

A multiplayer-themed game, Rainbow Six Patriots sees one team controlling the counter-terrorists, while the other team plays as the enemies. True to the series roots, both sides will have time available before a match begins to plan out how to attack or defend.

Either side can win when all enemy players are eliminated. The counter-terrorists, however, can score extra points by saving hostages. Contests play out across six total rounds; you'll play three as the counter-terrorists and three as the enemies. Ubisoft estimates rounds will take about three minutes, meaning the entire match will last around 18 minutes in all.

What happens if someone from your team quits before the match is over? Ubisoft is still working out details for such a situation, and no decisions have yet been made Remy and Marquis said. What they did confirm, however, was that Rainbow Six Siege will indeed be a full-priced game, not a free-to-play title.

GameSpot will have more about Rainbow Six Siege in the time ahead.

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