Onyx bolts (e)

Enchanted onyx bolts are runite bolts tipped with enchanted onyx. Onyx bolts can be enchanted through the spell Enchant Crossbow Bolt (Onyx) by a player with level 87 Magic. The spell enchants 10 onyx bolts at a time. These bolts are rarely used due to their cost ( coins per bolt) which exceeds the cost of Enchanted dragonstone bolts by about coins, but are frequently high alched. Enchanted onyx bolts have a Life leech special. This gives the bolts a chance of doing extra damage (20-25% chance from testing) and healing the attacker's Life Points by 25% of the base (disregarding damage modifiers) maximum hit of the hit that triggered it. This does not work on the undead, as they have no "life" to leech.

This effect can be triggered with auto attacks and abilities, with abilities consuming one bolt per activation.

The chance of the special attack occurring is increased upon the completion of the Elite Seers' Tasks.

The bolts also have a second passive which works with any ability, including threshold and ultimate abilities, healing the user for an amount equal to 25% of damage dealt. Unlike the other passive, this healing effect does not show any healing marks making it harder to notice and also will not consume any bolts.

They are tied with royal bolts as the third-strongest bolts in the game, both surpassed by ascension bolts and ascendri bolts.

Trivia

 * On 23 February 2010, a bug was leaked in which one could duplicate these bolts but was patched on the same day.
 * These bolts were untradeable when released, but a hidden update in 2007 made them tradeable.