Buy RS3 Skeletal helm
The Skeletal helm is a members-only Fremennik helmet made for mages in RuneScape 3. It is part of the Skeletal armour set. This is tier 50 Magic power armour, so it boosts your damage while it protects you.
The helm gives 146.4 armour and a 12.5 damage bonus. It also gives 0.9375% PvP damage reduction. To wear it, you need level 50 Defence and you must finish The Fremennik Trials quest.
Getting one on your own takes work. You can bring 1 dagannoth hide, 1 skull piece, and 5,000 coins to Peer the Seer in Rellekka. It is also an uncommon drop from Dagannoth Prime at a 2/128 rate. Buying it from Chicks Gold skips the grind.
The helm has more uses too. You can upgrade it into a superior skeletal helm with a Fremennik equipment patch. You can also disassemble it for Magic armour materials like Magic parts, Cover parts, and Powerful components. It is tradeable and lendable. Its examine text says it all: make your foes cower by wearing a skull as a helmet.