Instructions: 
Unpack files and drop into the Monster Hunter World folder.

Modifying:
If you want to pick a different hunting horn to change into the Sonorous Eisfyl, change the file names that inclide the "O15" number to match the corresponding ID below. For example, if you wanted to swap out the Shara HH, then you'd rename to files so that the ID number would read "016" instead.


Unique Models:
hue001 - Teostra
hue002 - Rathian
hue003 - Vespoid
hue004 - Nergigante
hue005 - Legiana
hue006 - Bazelgeuse
hue007 - Pink Rathian
hue008 - Deviljho
hue009 - Shreiking Legiana
hue010 - Seething Bazel
hue011 - Ruiner Nergigante
hue012 - Tigrex
hue013 - Nargacuga
hue014 - Glavenus
hue015 - Acidic Glavenus
hue016 - Shara Ishivalda
hue017 - Savage Deviljho
hue018 - Zinogre
hue020 - Yian Garuga
hue021 - Gold Rathian
hue022 - Rajang
hue026 - Guild Palace
hue027 - Brute Tigrex

Non-Unique (bases)

bs_hue001 - Ore (Metal Bagpipe)
bs_hue002 - Ore II (Thunder Drum)
bs_hue003 - Bone (Bone Horn)
bs_hue004 - Bone II (Anja Barone)
bs_hue005 - Kulve Taroth R6 (Gold Flute)
bs_hue006 - Kulve Taroth R7+ (Taroth Pipe)
bs_hue007 - Lunastra (Empress Roar)
bs_hue008 - Master Rank Iron?
bs_hue009 - MR Bone
bs_hue010 - Velkhana
bs_hue011 - Kulve Taroth (Kjarr all elements except below)
bs_hue012 - Kulve Taroth (Kjarr Paralysis + Water + Dragon)