Magic, otherwise known as bending reality to your whims.
Most magical skills consume spellpoints to create some effect. Different disciplines of magic have slightly different casting styles, effects, consequences and benefits. Witches and Sorcerers have the most affinity for the magical arts, but no classes are excluded from it.
Overuse of some types of magic can result in Magic Addiction. Some powers or commands, such as changing the weather are not part of any magic skills, but still require a certain level of magic to work.