Mostly just to show the rewards from this, since I'm not sure anyone's bothered with anything but word of mouth. No point going past Wave 20, as the rewards for the next cycle are listed, and there's nothing there. Intense would require some other players or effort on my end, since there's friendly fire and abusing AOE weapons isn't trivial there. And Alpha and Beta like to leap in front of you all the time. :P Too much trouble. Extreme and Insane, less feasible to go past Wave 10. Doesn't seem any point to keep going as well, even if you didn't already have the rewards.
Rewards: Air Machine Gun emote (Wave 10), Enhanced Reach 2 perk (Wave 20)
I'm pretty sure Enhanced Reach 2 drops randomly from campaign as well.
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