Attack Ghosts are enemies in Yoshi's Crafted World, it's a giant cardboard Boo Guy with a red body, a gold scythe, and a Shy Guy mask with evil, purple eyes they are only encountered in the levels Haunted Maker Mansion and Cardstock Carnival.
At first glance their presence is not immediately clear, but when Yoshi or other colours in his species is near one, it will suddenly appears, marked by a ghoulish laughter, and it proceeds to relentlessly chase him down, rapidly swinging their scythe the Attack Ghost is invincible but eggs can temporarily push them back.