The Haunted Roof is a slanted building-block with a blackish-grey brick-pattern that you can use as a roof-tile, a ramp-tile or for other purposes; it can be rotated by pressing and holding R (as the default key) while moving the mouse.
Blocks of Haunted Roofs can be obtained from Ghost Pigsies, Ghost Leafies, Ghost Rocksters, Ghost Chizzards or Ghost Mirus during Halloween event time. In 2016 this event started with update R35 on October 13th 2016 and ended in November 2016, with a short reappearance during the Festive Season Event. Recipes from this event can also be obtained in player-created adventures.
These non-aggressive ghost creatures only spawn in complete darkness at (ingame)night (starting a little later than 10:43 PM) and cannot be tamed, only killed. Ghosts usually flee from player characters and do not defend themselves.
Ghost creatures can be spawned on a Mob Spawner too, but in that case these non-tameable creatures won't drop anything at all when being killed, except for the stuff that players themselves have provided to the inventory of the Mob Spawner for the first creature to spawn.
Haunted Roofs can also be crafted in your Crafting Menu (default key "Q") or at Crafting Tables (that still exist in worlds created before R22 on September 16th 2015), but only after the crafting recipe has been unlocked after finding the according rare Recipe page in Loot Bags of ghost creatures during the Halloween event.
After learning this crafting recipe by right-clicking it in the inventory or dragging it over the character's model on the right side of the inventory, it will be permanently added to the crafting menu and as a rare recipe it will also "carry over" (be known) to all other Creativerse gameworlds after learning it.
To craft 8 (blocks of) Haunted Roofs at once, you'll need (as of R35 in October 2016):
- 2 Wood Rods made of any kind of Wood or Logs in a Processor
- 4 Wood Slabs made of any kind of Wood or Logs in a Processor
- 2 Bones that can either be made from blocks of Fossils in a Processor or be obtained from nearly all Creatures either by killing them or taming them, feeding and then harvesting from them
- 1 Stone Rod made of Stone, Limestone or Bedrock in a Processor