Depends on what you or me are calling hardcore of course.What's some of the most hardcore femdom games you've played?
I'm looking at the list but Karlsson's Gambit is tagged "medium to hard" while Theater of Sinners has "hard", so I'm not sure if the tagging is a good indicator.
But the most extreme ones are often not the best ones for me. For examples: i didnt like the gore part in the earliest versions of the void of defiance, but luckily the game got much better over time until its onhold now
Another example is hardcore femdom. People with cutted legs and such isnt turning me on. Its doing the opposite.
Examples that are still kinda hardcore`ish and good in my view are darktoz games and karlsons gambit