Oh, you should probably stop squealing and blinking about the whole new event thing and actually start cleaning up the streets. Those are nightmare creatures. They’re dangerous.
You’ll need a group of 3-5 players of level 10 or above, and once you’ve got that you can talk with the Golden Seraph NPC to start taking on the nightmarish enemies and beating them back. Rewards include several new headpieces and a new vehicle, so you have plenty of reason to smash things until they’re no longer nightmarish dangers striding across the land. They’ll go well with your new decorative tights, if you like. So break your “new event in Champions Online” glass and get to smacking some nightmares.
Source: Official Site