I know only what the high priests have spake after consulting the Stone Tablets of Ancient Prophecy, but by all accounts, pg is twenty feet tall, with fiery glowing eyes and fiercely flaring nostrils. His golden halo is shaped like a matched pair of parentheses, and his arrival is heralded by heavenly trumpets and a choir of angels.
I saw him once! But he was over 40ft tall, and 4 hands each with 20 fingers to be able to type more quickly. He is able to solve hard problems just by looking at them, and he is accompanied everywhere by 30 beautiful maidens.
I think this type of speculation is how we arrived at this, once upon a time (before the printed press, TV and the internet): http://bestiary.ca/
