Yurt the Silent Chief
After the Fool's Idol boss in the Tower of Latria, you will find a warrior wearing a spiked helm and using a shotel (a c-shaped sword) trapped in a cage. Do not let him out of the cage, or let him out and kill him. He is Yurt the Silent Chief, and if you let him free, he will return to the Nexus and one-by-one kill the NPCs who sell you Miracles and Magic, which will make you unable to learn new spells/miracles or change which spells/miracles you are using.
Added by: naraku2099 Oct 15th 2009, ID#2075