Also known as "Master of Fears" This ghost's basic form resembles a smaller version of a pumpkin with an extra leaf part underneath its belly. This ghost's booster mode adds a carving in its mouth, glowing orange from the inside. It has four thorns as its roots and two plant leaves as its hands. Grump King is a plant based, shapeshifting, illusionist "Master of Fears" pumpkin ghost who has the power to show a person's fear and turn them into halloween monsters.