Michael Morbius was a gifted, Nobel Prize winning chemist, with much wealth and a beautiful fiancee whom he happend to love dearly. However, none of this mattered when he learned of the rare,incurable blood disease that he had contracted . Frantically, he searched for a cure, eventually experimenting with the enzymes of vampire bats. This worked, but with a terrible side-effect: Morbius now had to feed upon the blood of the living to survive... he had become a living vampire!
Morbius is termed as a 'living vampire' in that he is not dead, like true vampires are. Morbius does have to stay away from the sunlight, but does not sleep in a coffin. A stake to the heart wouldn't kill him, and he can't turn into a bat. He does, however, have a pair of large fangs and a thirst for human blood.
After becoming a vampire, Morbius discovered that he had the ability to fly. This ability was not explained until Morbius #3, when Morb's friend, Jacob, performed a cat-scan on him. Jacob discovered that Morb's brain had been rapidly evolving ever since he had become a vampire, and that he had the ability to tap into parts of the mind that normal people do not. This explained his ability to defy gravity.
In Morbius #1, Morb was infected with demon blood, which caused some odd changes in his physiology. His basic cell structure had begun to take change (as seen in Morbius #3). He also gained hypnotic powers, which he used upon his prey. He used these on Spider-Man in issues #4, to make him forget the events of their battle. Morbius also gained the ability to extend his limbs, or lose his shape, and become blob-like for short amounts of time. This power increased more and more from Morbius #1-20, until the demon part of Morbius was killed.