Read from the World of Warcraft client build files (JournalEncounterItem, JournalEncounterCreature, Achievement) and the Blizzard Game Data quest API.
How Serpentskin Splashers Compares
Who It Suits
Cloth is the armor type Mage, Priest and Warlock wear. With Intellect, Serpentskin Splashers suits Discipline, Holy and Shadow Priest; Arcane, Fire and Frost Mage; Affliction, Demonology and Destruction Warlock.
Transmog Sets
Serpentskin Splashers is part of the transmog set Frilled Harbinger's Vestments (Priest, Mage and Warlock only). The other 16 pieces:
Blizzard numbers items as they are created, so the named items next to ID 169925 (169919 to 169930) were usually added in the same batch as Serpentskin Splashers: the same quest line, zone, vendor or reward set.