Minecraft wiki entry for Skeleton, associated text: In Java Edition, during Halloween (October 31), skeletons have a 22.5% chance of spawning wearing a carved pumpkin and a 2.5% chance of spawning wearing a jack o'lantern. If these skeletons are killed using a tool enchanted with Looting, the pumpkin or jack o'lantern can drop with a chance equivalent to the level of Looting, up to 3 percent chance with Looting III.