Corken have no eyes or ears, instead using their extremely powerful and minutely discerning sense of smell. They smell with the suckered surface of their large tentacles, so if the tentacles are removed somehow, they will wander around aimlessly for a while, then give up on life and just sit down.
The traditional old-fashioned preparation of the Holiday Corken is on the left. On the right is the more recent style, where the tentacles have been removed and prepared separately, usually as a fried treat as well as an ingredient in other dishes. A few people in larger cities, such as Cooperton or Frippert, now put tentacle in the stuffing, but this is frowned on by all but the middle and upper classes.
Also, upon doing an image search to see who had done that top pic that had been sitting in my drive forever, I discovered somebody else had made a different (though obviously similar) creature for 5e. Here is their blog/campaign diary: skaldforge.wordpress.com. And here I thought I was the only one this odd. Well, not really.