Provide one of the Craftsmen in Minas Tirith with materials.
A mighty war horn.
Take a tusk from one of the boars in Fangorn Forest to the craftsman on level 2 of Minas Tirith. Return later when he has finished.
Blowing the horn will increase your tactics for a short period, each blow of the horn has a random chance of breaking it.
A broken horn looks the same as a working horn, so the only way to know if the horn is broken is to try blowing it.
The craftsman will only appear in Minas Tirith during the daytime.
Go directly north from Edoras until you find Fangorn Forest. Explore this area until you come across A large bristle haired boar. Kill this boar and then take the A short but sharp tusk from the corpse to craftsman (Humgar, an experienced craftsman) in the workshop of Minas Tirith level 2. Return 15 minutes later and he will reward you with the horn.
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