The enhanced excalibur is a very important weapon for many long term PvM situations. The special attack heals 500 life points over the course of about 12 seconds. The special also raises the user's defense to 112 (assuming their defense level is 99). Since it takes 5 minutes to regain 100% special attack, the special can be used every time a player needs to drink a dose of overload. Since an overload does 500 damage, this special negates it's effect. The special attack's animation is shown below.
To purchase the enhanced excalibur, a player must be able to access the prestige 9 island. Getting to the prestige 9 island is simple (as long as you have prestige 9). Remove all armor and weapons, and then talk to the wise old man at ::home. After arriving on the island, talk to the forester.
The enhanced excalibur is the first item in the shop, and can be purchased for 200 fist of guthix tokens.