Shandalar is an incredibly powerful mage who lives in a skyship just east of Ulgoth's Beard. He will ask you to retrieve his cloak from a magical ice prison. You can agree, in which you will immediately be teleported to Ice Island with a wardstone that will take you back to Shandalar once you have recovered the cloak. However, if you've killed Shandalar's daughters in the Estate of Oberon, you will be sent without choice.