The crystal bow is an attuned elven weapon, required for the Roving Elves quest to be completed. It is a ranged weapon with an improved damage and accuracy bonus when crystal armour is equipped.
Ilfeen is able to re-enchant partially degraded crystal weapons into full enchanted items for a cost depending on their charge. She can be found teleporting back and forth between two clearings in Isafdar (from the lodestone, take the northeast path, jump over a leaf trap, go north to the teleport point, then turn right through a dense forest).
Players can also purchase new crystal bows from Islwyn just north of the south-east Prifddinas bank for 900,000 coins. Unlike the recharge price of Ilfeen, this price does not decrease as the crystal equipment degrades.
When a crystal weapon or shield is re-enchanted by Ilfeen, it becomes non tradeable even when it is fully charged. This means that when it is dropped, it will remain untradeable, and players will have to buy a new one on the Grand Exchange for a small fee.
Previously, crystal equipment degraded gradually as it was used in combat, with each kill using a charge and eventually dropping it to a seed. However, with the Evolution of Combat update, this has been revised and now only charges are used when attacking a target.
The PvP death value of crystal weapons and shields has been revised to increase their lifespan and the harmonic dust cost to create attuned crystal equipment has been reduced. Attuned crystal weapons and shields now degrade to a seed, rather than reverting to dust.