Between its imaginative weapons and outlandish premise, Sunset Overdrive already sounds pretty zany. But wait until you get a visit from the Chaos Squad.

Sunset Overdrive's 8-player co-op mode was confirmed at Microsoft's E3 2014 press conference alongside an October 28 release date. We went hands on with the new horde-like mode, Chaos Squad, and it's just as loose, fast, and fun as the bits of the single-player campaign we've already played . This is a multiplayer mode that doesn't take itself seriously.You and up to 7 friends can face off against waves of Sunset Overdrive's infected enemies. Remember, these are people who became too addicted to FizzCo's toxic energy drink and are now mindless monsters. Your crew has two vats of Overcharge Delirium XT, and the baddies want it. The goal? Don't let them have it, of course.Most enemies won't give you too much trouble alone, but together they can cause quite a panic. Occasionally, huge enemies like the towering "Hurker" barrel through the front lines and try to get up close and personal with you. Focusing fire on them with your friends is a good way to get them out of the fight quickly. For the rest of the mobs, there are plenty of silly weapons -- this is Insomniac, after all, developer of Ratchet & Clank -- that you can use to clean house. One fires propane tanks, to give you an idea. When things were exploding and erupting all around, the game looked great and the frame rate didn't dip for a second.Though you all have a common goal, you're still competing to earn the most points, and you earn them much like you do in the campaign -- by killing with style. The map I played was filled with rails to grind, objects to bounce from, and things to explode. It's acceptable to run around on the ground and treat Sunset Overdrive like most shooters, but it's way more interesting to rain down icy death from the rails above before jumping down and shattering your foes.The demo also revealed light tower defense elements, like the ability to place spinning blade traps. Insomniac wasn't ready to talk about the mode's economy yet, so I was only given one trap to use wisely. I found the routes toward the Overcharge vats that the infected seemed to favor and placed the obstacle in the way.Chaos Squad can be accessed from Sunset Overdrive's single-player mode by entering a photo booth and taking a selfie. Your single-player character, which can be male or female, and customized in any way you'd like, is available to play in the co-op mode as well. And any bonuses you earn from co-op, including new weapons, transfer back into your single-player campaign for you to use immediately.For more on Sunset Overdrive, stay tuned to IGN during E3 and keep an eye on our Sunset Overdrive wiki

Brian is an associate editor at IGN. This is his first E3. You can follow him @albinoalbert on Twitter.