Willow pyre logs may be used during the Shades of Mort'ton minigame to cremate the remains of Loar, Phrin and Riyl shades. They require level 35 Firemaking to light and grant 100 Firemaking experience when used to cremate a shade.
To make willow pyre logs, players must first obtain some sacred olive oil. Sacred oil may be made during the Shades of Mort'ton minigame or the Shades of Mort'ton quest. To create the oil, players need to purchase normal olive oil from Razmire Keelgan's store in Mort'ton and then help to restore the temple that lies to the north of the town. Once the temple is rebuilt, players may light the altar in the centre of the temple and use their olive oil on the fire. This converts the ordinary olive oil into sacred oil.
Once the sacred oil has been obtained players will need to use three doses of it upon some willow logs. These logs will then become willow pyre logs and grants 12 Firemaking experience.
Once a player has obtained the willow pyre logs, they may use them, along with a set of shade remains (Loar, Phrin or Riyl), upon one of the numerous funeral pyres located to the south-west of Mort'ton's centre. If the player has a tinderbox in their inventory they may then light the pyre and, by doing so, release the spirit of the shade.
The player will see an animation of the shade's spirit floating up, away from the pyre, and then either a key or a stack of coins will appear on the pedestal nearby. The type and level of the key is dependent on which shade remains the player has burnt, with higher level shades leaving higher level keys.