The villain, Sauron, was originally to be a werewolf, but the Comics Code Authority forbade this. As a reference to his origin, however, Sauron's alter ego is named Karl Lykos. The scientific term for being a werewolf is Lycanthropy.
The first episode with the new opening and without the credits of the main X-men.
In the comics, Sauron takes his name from the titular villain of J.R.R. Tolkien's The Lord of the Rings, which was popular and still very new in 1969 when the character was introduced. The X-Men's usual nemesis, Magneto, was played in the live-action films by Ian McKellen, who went on to play Gandalf in The Lord of the Rings films.