It was originally written during the reign of Caesar Augustus (27 B.C. - A.D. 14) by his chief advisor, the original Magus. It was the most powerful and comprehensive book of mortal spell books in existence. There are spells that may have even been contributed by Merlin himself. She used one of the spells that she had thus stolen to help create Coldstone, and another later on to place her "stone by night" curse upon New York. When the gargoyles had to leave Castle Wyvern for the Clock Tower, they took the Grimorum with them One page is known to still exist, and it is in Demona's possession.