"Wear it like royalty."The Spider Queen's Crown is a headgear item dropped exclusively by the Spider Queen. This item currently has the lowest drop rate in the game after dyes and the Old Fishing Rod, at a tight 0.1% chance, explaining both its value and rarity.
It is mainly meant to be a vanity item, as it does not give any boost to defence, nor does it have a level requirement. However, blessing the crown using The Orb in Nilgarf gives a very potent +2 boost to every stat, as well as tinging the item's border yellow, which is an indicator to well-upgraded items. This could cost a substantial amount, though.