Glissa

Glissa buys life runes from you for 1,000 gp each. She can also change your respawn point to Prifddinas. She sells death, nature, astral and cosmic runes.

You can start the My Dark Brother quest by talking to her.

After doing The Princess and the Warrior quest, you can set a fight up with her. Her combat stats are the same, but the attacks are different. She uses magic and range only. Her mage attack is a 20 second entangle doing 100 damage each second (a total of 2000). This spell cannot be nullified with Protect from Magic, nor can the damage be reduced. Her ranged attack are throwing (crystal) knifes at a very very high speed (doubled speed of normal throwing knifes). These do about 400-800 damage each. This is not much damage, but the speed and amount counts up and your life points may soon be at 0. However, this damage can be reduced to 200-500 damage with Protect from Ranged. The best method to kill her is to use range her while having protection from range on. If you manage to defeat her, you can get 110,000 Ranged and Magic exp on your first kill. You get 11,000 for any further kills (once per day).

If you have a strong friend or partner, you can ask her for a 2 vs 2 fight against her and Sarixs.