Now that you point to the hard mode version of that damned broken horrible boss, i just noticed that those special items aren't ported to hard mode if you got them in normal mode, it looks like you'll have to re-earn them for the hard mode too .
Too much self inflicted pain for me
I had some die faces that were keys with other stuff, but didn't manage to roll them, so I had to increase my attack multiplier before the capture so I could kill the chest with 3 single swords. Also, only managed to roll the capture on the last die roll of the last round.
Getting a rollover fang on the first die was pretty nice, because 3 attack (with the relics I chose) is enough to take out the monks. Adding lifesteal and stun (cost 2 white gems, but worth it) to that was mostly just for fun. Adding it to the double axes was what kept me alive.
Edit: The chaos realm counts as beating a level for unlocks. The 12 hard mode levels unlock is a weird one. It mutates one enemy (possibly a boss) each wave, which increases your score and xp gained from that enemy. You also randomly gain a multiplier, gem, gold, temporal gold, shield, or health when you defeat a mutant. Probably useful for those easy mode levels you have difficulty getting that 5th star on, assuming you're going for all of the possible stars with one character.
Edit2: Did you know there are more than 8 classes? I just unlocked this beauty: