Hexcrest

The Hexcrest is a unique Slayer item dropped by Jungle strykewyrms. In order to equip it, a player must have a Magic level of 20, a Defence level of 10, and a combat level of 40. It boosts the player's Magic strength by 15% against their slayer task monsters. It can be combined with the Focus sight and Slayer helmet to form a Full slayer helmet. With the Staff of light, a 7 level boost from an Extreme magic potion, Overload potion or Wolpertinger, being in Kuradal's Dungeon and wearing a Ferocious Ring, and a Hexcrest or Full slayer helmet worn against an assigned slayer monster, the theoretical (if all of those things stack, which is not confirmed at the moment) damage percentage boost would be 51%. For already powerful spells like Fire Surge or Ice Barrage, the resultant Magic damage could be approximately 422 or 453, respectively, on a slayer task with a 51% boost. Damage in the 900s is possible against Ice strykewyrms using Fire Surge.

This item is NOT lendable.

On the day this item was released, people were paying an upwards of 25 million coins, utilizing junk trading, to buy them. It crashed in the next few weeks in the Grand Exchange, falling over 60% in 4 weeks.

Trivia

 * The Hexcrest appears higher on a player's head when seen in-game than it does in the equipped item window.
 * As of March 28, 2010, there is currently a glitch in the grand exchange market watch that oversizes the hexcrest's icon. The icon is so large that it overflows off the square and parts are not visible.

the boost of a hexcrest does affect the magic attack of the saradomin sword special attack