Furnace (Look Outside)

The Furnace is an optional boss found in the center of the Sewers. It is a witness to the Visitor who, like Placide with the pipes, has fused with the central furnace of the Apartment Building. It has frozen over due to mutated Ticks parasitizing the long tentacles that extend from it into all corners of the sewer. Killing all the ticks, including Tickle, will wake Furnace, allowing it to be battled. There are eight tentacles, extending in all cardinal directions, which can be followed to find the rough direction within the sewers that any uncleared tentacles are in. Cleared tentacles will begin to emit a molten glow from within. The Furnace can be fought without killing Tickle by inviting him to infest Sam. Killing the Furnace gives you Furnace Edge, a Fire melee weapon with 26 Attack and one of the only sources of reusable Fire damage.