Amos var Ypsis

Amos var Ypsis was a mage specializing in djinns. According to a book written by him, he had managed to tame a djinn and harness its power.

Biography
A powerful mage, var Ypsis was able to tame a djinn and use it as a source of Power. He published his findings in a tome which ended up in the Imperial Library, where it was eventually discovered by Yennefer.

Var Ypsis's last expedition was to Skellige. He travelled to the village of Larvik on Hindarsfjall, where he had contact with the locals. With his djinn in tow, he departed Larvik by ship and sailed to Ingdalen Isle before an unusually powerful storm broke out. In order to get out of the storm, var Ypsis made a wish to his djinn, which teleported its master, along with part of the ship and a section of the seabed, to a mountaintop in northern Ard Skellig. Due to a very rough landing at the destination, var Ypsis was knocked out of his boots, before being crushed to death by a falling bookcase inside his cabin.