Very cool update i know that there's still a lot of stuff to be worked on until the update is launched officially, but i've also got an awesome idea for the crab king:
-Dark oyster: Obtained in the same way as sunken teasures, but only during night, and having higher chances of being found during moon, and they're giant oysters which can be carried around, and a player can give it a pearl, that after some in-game days the oyster will turn this pearl into a dark pearl
-Dark pearl: obtained from shadow oyster, it can be socketed to the king crab in the same way, but the effects won't be the same...
-Possesed crab king: An even harder version of the king crab, turned from king crab once a dark pearl is socketed instead of a regular one, in this form crab king eyes turn black with the pupil red, it's legs will get really extended, making him able to walk around, whitout staying in the same place, and even walk on land, once defeated his legs would return to the original size and he would do the regular defeat animation.
His attacks will stay almost the same, but he can now do a melee attack with his claws, and he no longer have to restore it's shell as smaller crab claws comes out of it to keep repairing it instead, not sure about how will the geyser and imposing claw attacks would work on land, i guess that crab king would only use spells that work on land in this case, like the chilling one.
Of course that all of this would be worth an exclusive loot different from the original king crab, i'm just not sure about what could it be, and there would possibly be a way of obtaining more than 1 pearl, or the dark oyster would require another item instead