Dwarf brew is a special beer used in the later stages of the Underground Pass quest. It is obtained by using an empty bucket on a barrel behind Klank's house deep in the dungeon west of West Ardougne.
The brew is used to light a pyre over the tomb of Iban, cremating his remains and turning them into Iban's ashes which must then be used on the doll of Iban to create his effigy.
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