Colossal Valiance Circlet (F) is crafted with Hillwen Engineering in Mabinogi. This page lists everything needed to make it, checked against the game as it exists today. The interactive planner lives in the Hillwen Companion.
Recipe availability
Colossal Valiance Circlet (F) is a rank 6 Hillwen Engineering recipe with a best success rate of 98% at rank 1 and dan ranks.
Materials
Each craft uses
1× Helmet — Craft basic helmets like Bascinet or Steel Headgear through Blacksmithing.
10× Hillwen Alloy
8× Valiance Metal Shard — Hard/Elite Shadow Mission reward or Advanced Hard Mode Dungeon reward
3× Sub-Zero Coolant — Possible reward from Elite Shadow Missions like All-Out War or Sniper War.