Anyone can use anything. You can cast a fireball, wearing plate mail (don't have a heart attack, purists!). There will be logical modifiers to doing unusual things like that, but if a player wants to do it, we want them to do it as long as game balance isn't unreasonably skewed.

Super hardcore, as in the nudity/cannibalism featured in Mortal? I have zero interest in it because I find most virtual 'gore' to be puerile and comical. The community may think differently than me.

Dismembering a player after defeating them in PvP, and selling their 'parts' on the AE? No, that wasn't discussed.