Year Three of Rainbow Six Siege kicked off with a bang this week, driving back players to the game in record concurrent numbers thanks in part to a new cooperative component called Outbreak. This wild departure for the Rainbow Six franchise introduces a supernatural threat to the tactical shooter that feels more like a Left 4 Dead expansion than anything tied to the Tom Clancy universe.

A dramatically divergent offering, Outbreak doesn't do anything to bring back the old-school Rainbow Six fans who long for the carefully planned missions and measured tactical engagements of the past. With its adoption of G.I. Joe-style hero characters and now a full-on zombie-outbreak theme, it's clear Ubisoft is comfortable evolving the series away from its military-sim roots and moving more toward the comic-book end of the entertainment spectrum. 

This trio of cooperative missions takes place in the small rural town of Truth or Consequences, New Mexico. After a mysterious probe crash lands and a virus starts infecting the populace, Team Rainbow is sent in to neutralize the threat. The virus turns humans into a variety of grotesque mutants, each with a unique attack style. Grunts charge and swing their sharp tentacles wildly, while the agile, wall-climbing Breachers detonate to inflict massive damage or take out your fortifications. Most missions culminate with showdowns against dangerous bosses like the towering Smasher or formidable Apex, which can cast waves of enemies your way and momentarily blind operators with a projectile. The visual design of these enemies is impressive - I'm surprised how much attention to detail went into a mode that only lasts a month -  and learning how to prioritize threats as they swarm is key to surviving.

Rather than give players access to the full list of operators, Ubisoft restricts it to 11 characters (two being the new operators introduced in Operation Chimera, Lion and Finka). Fan favorites like Ash, Buck, and the hapless Tachanka are among the options, and some have been tweaked to give them more offensive punch. For instance, defenders who normally have defensive tools like razor wire swap them out for grenades. 

While the supernatural enemies and truncated operator list may be drastic departures, the mission objectives stay much closer to the Rainbow Six norm, like planting detonation charges to wipe out a nest, escorting a doctor through an infested medical facility to gather critical supplies, and finding the source of the outbreak. All three environments are much more open than the typical Rainbow Six Siege map, giving players the freedom to take their fights outside should the close quarters of a ramshackle house get too hairy. Curiously, the story never culminates to a natural endpoint where the outbreak is neutralized or spreads beyond the confines of the quarantine zone. Perhaps Ubisoft intentionally left Outbreak open-ended, giving it the flexibility to extend the narrative should it resonate with players. 

Missions alternate between attacking and defending sequences. After shooting a path to your objective marker, you have a split second to fortify your position with wall fortifications and barricades before the enemy onslaught begins. Having at least one operator who can bolster your defenses is a wise move considering some of the more formidable infected eventually make their way into these cramped quarters; anything you can do to stymie the initial onslaught before the heavies arrive helps immensely. Given you're always setting up a defensive perimeter on the fly, Ubisoft wisely sped up the time it takes to set up barricades. Just like the competitive multiplayer, the pulse-pounding action keeps you on your toes and demands communication between teammates to survive, especially on the Pandemic difficulty setting that enables friendly fire and adds a larger number of deadlier enemies to the fray.

Missions take about a half-hour, but the rewards are curiously stunted compared to the competitive multiplayer. Earning only 300 renown for completing your objective feels like a rip-off, and may discourage players from sticking around to play more. The only tangible rewards outside of paltry renown gains are a handful of Ubisoft Club challenges that yield Outbreak-themed charms.  

Taken at face value, these new cooperative missions are a welcome curveball for the series. I doubt many players will continually replay Outbreak given the meager rewards, but it's a fun change of pace nonetheless. If you like the sound of playing through a Left 4 Dead style mini-campaign (hey, at least someone is carrying on that tradition), you have 25 more days to check it out before Ubisoft retires this limited-time engagement. And that's the most curious decision Ubisoft has made with Outbreak. This isn't a small development investment like adding the Predator to the pre-existing world in Ghost Recon Wildlands; the amount of work that went into its level and creature designs seems dramatic for an event with such a short shelf life. Making the mode permanent, continually adding new content, and pairing it with terrorist hunt could open the game up to a new audience that prefers cooperative experiences to core competitive multiplayer.