A boss idea, consisting of my favorite enemy in the game: the Chromalisk :)
I don't care that we've already had a beast boss, it's not about making a boss for every monster type. it's about having unique and fun play. So my suggestion is simply this. A large 'mother-hydra chromalisk' (and by hydra I don't mean mult-headed, you'll soon find out). This fearsome looking chromalisk is, as stated the mother of all chromalisk, and will have a multitude of eggs that constantly hatch small nuisance chromalish, much like the bots in the twins dungeon. The boss has a few unique attacks. Her main and very important ability is to randomly rotate through colors, each representing a status effect, like a slot-machine, during which the beast is still invincible. Once a color has been chosen, the Hydra-chromalisk will rotate spewing a line of globby-goo that will inflict a small amount of damage and the based status effect. After a rotation or several, the boss will stomp around and begin licking about with it's massive tongue, and if your knight should be unfortunate enough to be hit, (although this should be easy to dodge unless you are stunned, frozen or shocked) the Mother- Chroma will gulp you in, harm you, heal herself a small portion of health, and spew you back out. The knights main task during this period is to trick her into licking one of the nearby trees, and her tongue will get stuck. During this period the Knights must swing at the tongue, doing so will knock her out for a few moments, in which time a knight (one not all) must walk into the belly of the beast and do your damage ( during this time the mother will not be able to harm you, and once she awakes you will be spewed out with no damage done). Another unique idea I present to you is that while the young chromalisk emerge, any spewed on during the course of the hydra rotation will attain the status type variant as their source of spew weapon.
My suggestion for weapons that may be won using tokens from this boss are as follows:
A blade that act like a chroma tongue, when swung it begins small and stretches out further than any other sword. Perhaps the first swing grabs an enemy, and pulls it to you for a second swing? Like a yo-yo.
A 'Mother Chroma-scale shield' or 'mirror shield' that will block piercing, but with a unique effect, should an enemy attempt to harm a knight while blocking, any status that monster may have tried to afflict, the shield is now resistant to. For example: Should a Lumber swing at you and you succesfully block, your shield is suddenly pretty decent at resisting stun. (although I use lumber in this reference and I realize that they are one of few monsters that can afflict two statuses, I would suggest that the shield only be able to absorb one status, as two would be too many.) The idea is, that when sward against a group of monster afflicting one status, you will become resistant to it while blocking, but should a different monster with a different status hit you, you will be resistant to the newer status, and lose protection from the old.