From Daily Deal. Hopefully this'll make my support priest's life easier now that I can actually have a nimbus warrior tank those big monsters.
Don't worry, I'm pure PvE player :3 All elves party at the moment .- . it's quite tough but hilarious at times (like when I'm only left with a wizard and 2 festering zombies with resistant hide, so I have to run around until I draw rock spike and hope the thing doesn't have another shuffle to get out.
Impenetrable Nimbus is simply lovely against the AI, then. Few AI-controlled monsters have a realistic chance of removing your attachments and it will happily waste attack cards against it.
If memory serves, it's even better if you have something like Mimetic Crown or other in-hand card which produces a beneficial effect when it reduces damage. I seem to recall that the armor is checked first and only afterwards does the nimbus zero damage, so attacks that had no chance of hurting you can give you free attack cards or the like.
I learned that lesson in a slightly hard way (used Nimbus to try and save my Warrior's armor from getting destroyed by Shredding Strike...;- ; )