Yeah I played through Khazan. It's a pretty good game, level design is ok but the bosses have too much HP, the fights are too long and require you to play perfectly the whole time, you can easily die if you make 1 or 2 mistakes despite playing perfectly for the rest of the fight.
I played the game on normal difficulty until I switched to easy mode at the final boss to get the game over and done with. The final boss on easy mode was still just as hard as any dark souls game. I wasn't having fun fighting it, I was worn out by the end of the game.
Easy mode does not make the game too easy which is good. Wish I just played most of the game on easy, probably would have enjoyed it more. I was spending hours on each boss, all of them are very hard on normal, every boss in the second half of the game has the same difficulty as the final boss or DLC boss of any other souls-like.