A new mode will be available in Skylanders Trap Team. It seems to share some similarities to modes we've seen in the past, but it is different.
Kaos' Doom Challenge is a sort of tower defense game. There is a special chest that you need to protect from the enemies spawning from one or more entrances to the level. Occasionally you may have some assistance from some friendly turrets, but it's mostly up to you.
Here's a quick overview of Kaos' Doom Challenge…
Here's what happens when you fail… (I would actually recommend watching this video all the way through as it answers a bunch of questions.)
And here's what it looks like when you succeed…
A few months ago we got a sneak peek at the Trap Team Achievements. At that time we weren't quite sure what all of them meant. Now we know what Kaos Mode is.
I think earning 50 Stars in Kaos Mode could actually provide a little challenge. This is not a bad thing.
Watching the videos above should answer most of your questions about the Kaos Doom Challenge, but if you still have questions feel free to leave them in the comments below.