Obelisk of Incineration Blueprints
From MHWiki
These blueprints detail how to construct a fiery trap that deals arcane damage. Obelisk parts and 2 scraps of metal form a staff that draws power from a single piece of coal. Splintered wood set alight starts the flow of energy from the coal.
Obelisk of Incineration Trap Blueprints can be purchased in the Catacombs [General Store]] for 45,079 gold and is used to craft the Obelisk of Incineration