Read from the World of Warcraft client build files (JournalEncounterItem, JournalEncounterCreature, Achievement) and the Blizzard Game Data quest API.
How Hardened Greathelm Compares
Who It Suits
Plate is the armor type Death Knight, Paladin and Warrior wear. With Strength or Intellect, Hardened Greathelm suits Arms, Fury and Protection Warrior; Holy, Protection and Retribution Paladin; Blood, Frost and Unholy Death Knight.
Transmog Sets
Hardened Greathelm is part of the transmog set Battlegear of Guiding Light (Paladin only), which the Appearances collection lists in 3 versions. The other 13 pieces:
Ensemble: Fel-Automaton ExoplateID 189938 · Consumable"Please note that the warranty does not cover issues related to personal fel corruption."
Items Numbered Next to Hardened Greathelm
Blizzard numbers items as they are created, so the named items next to ID 113910 (113905 to 113915) were usually added in the same batch as Hardened Greathelm: the same quest line, zone, vendor or reward set.