Gosaku's Helmet - Refined is a helmet that unlocks when Gosaku's Armor reaches level III. Upgrade the armor and it is added to your gear.
Upgrade Gosaku's Armor to level III. The helmet unlocks right away.
You can wear it with any armor.
Gosaku's Helmet - Improved
Gosaku's Helmet - Improved is a helmet that unlocks when Gosaku's Armor reaches level II. Upgrade the armor and it is added to your gear.
Helm of the Lower World
Helm of the Lower World is a helmet hidden on Iki Island. It sits in a secret storage room on the Mongol warship you dock during "Jin from Yarikawa", at Fune's Refuge.
Helm of War
Helm of War is a helmet earned by finishing the Shrine of Ash, one of the Wind Shrines. The same shrine hands out the Spartan mask, so you get a full look in one run.
Image: Sucker Punch Productions / PlayStationHelmets
Helmets are cosmetic headgear for Jin that sit in the Helmet slot of the Gear menu. You get them from tales, armor upgrades, one shrine and a few hidden spots on Iki Island.