A magical, malevolent crystal entity of slime that has infected the town.
The slime crystal has a large amount of health, and shoots triple poison balls with a limited range. It appears in a room with a set arrangement in a sewer level, with four poison spore mushrooms and four dashing blade traps, spiderwebs and metal piles around the room.
Usually player weapons are able to hit the crystal staying at one spot without getting hit back, but the dashing blade traps and mushrooms become troublesome distractions. So if your weapon range is not long enough to snipe the crystal, kill the mushrooms and stay away from the edges where the blade traps hit you.
On the crystal's death, it should drop a gold crown of 1000 coins and a health potion, healing 25hp. Bear in mind the door of the room does not close when you enter so feel free to ignore the crystal.