In a poem, this person retired to the woods of King Rhydderch (“RUH-therck”) where he lived in a house with seventy windows. This person was trapped under a large stone, a tree, or in an invisible tower by Viviane. This person (10[1])revealed that Vortigern’s (10[1])tower couldn’t (10[2])be built because a red and a white dragon were battling below it. (10[1])A story by Geoffrey of Monmouth explains that this person moved Stonehenge (-5[1])to honor the older brother (10[1])of Uther Pendragon. T.H. White fictionalized the idea that this person lives time backwards and is continually growing younger. This mentor of Morgan le Fey sealed the Sword in the Stone. For 10 points, name this (-5[1])magical advisor to King Arthur. (10[2])■END■