This weekend at the Wizards of the Coast "
Stream of Many Eyes" event I got my hands on a copy of
Mordenkainen's Tome of Foes, which is "built on the writings of the renowned wizard from the world of Greyhawk." That magic-user Mordenkainen, one of Gary Gygax's earliest and most famous characters, has been with us since the start of
Dungeons & Dragons. Gygax jealously guarded the statistics of Mordenkainen in later years, but this excerpt from a mid-1974 letter shows his favorite character as he was specified in his prime.