Alpha is the name of two characters in the Marvel Universe.
Alpha (The Ultimate Mutant)
The "Ultimate Mutant," a creation of Magneto. This creature was incredibly powerful, as its name implied- it reverted Magneto and the Brotherhood of Evil Mutants to infancy before setting out for space. Out there, he encountered another being known as the Futurian, who became his mentor as they travelled the galaxy. Some time later, they were captured by the Stranger, who placed them in one of his experiment zones. They have apparently resided there ever since.