Some magicians, even after training, continue their education by learning more spells, inventing new ones (and new magical objects), or rediscovering ancient spells, beings, or objects.[citation needed] For example, Dr. Strange from the Marvel Universe continues to learn about magic even after being named Sorcerer Supreme. He often encounters creatures that haven't been seen for centuries or more. In the same universe, Dr. Doom continues to pursue magical knowledge after mastering it by combining magic with science.