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. (10[1])This person revealed that Vortigern’s (10[1])tower (10[1])couldn’t be built because a red and a white dragon (10[1])were battling (10[1])below it. A story by Geoffrey of Monmouth explains that this person moved Stonehenge to honor the older brother of Uther Pendragon. (10[1]-5[1])T.H. White fictionalized the idea that this person lives time (-5[1])backwards and is continually growing younger. This mentor (-5[1])of Morgan le Fey sealed the Sword in the Stone. For 10 points, name this magical advisor to (10[1])King Arthur. (10[1])■END■