The female dullahan. At first, it was meant to be male, but I thought a female version of this creature was much more interesting. I was really pleased to see it on the tutorial's final cut (Which is free to download on the website).

It is a VERY tough enemy, is slow but packs a punch, is swings its axe with devastating power and then hammers it into the ground, holds its head and it delivers a very powerful screaming attack that deals great damage and leaves the player stunned.