Excalibur is a member's only quest weapon, that was once and still is wielded by the legendary King Arthur. To wield this weapon, the player needs at least 30 Attack. Its stats are the same as those of a mithril longsword. It also has a special ability activated by right-clicking it while equipped, which raises the user's defence by 8 levels.
To receive an Excalibur the player must complete the Merlin's Crystal quest to a certain point. It's seen again in the Holy Grail quest.
This item is never retained upon death and players will have to return to the Lady of the Lake to get it back. She will charge 500 coins to return it.
The Lady of the Lake will turn this weapon into the Enhanced Excalibur after completing all achievements up to hard Seers' Village achievements. Players cannot mount the weapon for display in their quest hall after the enhancement. Players may receive another Excalibur for 500 coins by talking with Lady of the Lake, even if they have mounted one in their house.
On 20 January2009, the inventory image for Excalibur was updated to coincide with the release of the Seers' Village Tasks. Players who had Excalibur, or did the quest, before the update still have the old inventory model, even when trying to buy a new one. This was fixed on 29 September2014.
Before the Evolution of Combat update, despite having an adamant longsword's stats, it required only level 20 Attack.
Excalibur, as a main hand weapon, technically has a higher damage rating than Enhanced Excalibur, an off-hand weapon. However, the latter still has a far superior accuracy rating as well as other handy buffs.
Previously, players had to be wearing the Seers' headband 3 when speaking with the Lady of the Lake in order to have the Excalibur enchanted.