Rastakhan's Rumble Guide
Can't attack or be attacked while damaged.
I tried to adapt it to make it immune to hero powers...but didn't read well enough that it would only be immune to "targeting" by hero powers...dumb on my part.
Lol poor you :D
Man. Cool. Totally a real card.
bosses encounter :)
Most likely the Lady Deathwhisper encounter
As per knight of the frozen throne site:
Deathwhisper has dragon-napped Valithria! Save the dragon, save the world.