Dark Magic is a form of witchcraft that draws on malevolent powers, and may be used for dark purposes that deliberately cause harm in some way (e.g. to injure or kill, to cause destruction or misfortune, or for personal gain without regard to harmful consequences). In popular usage, the term "dark magic" is often used to describe any form of magic that goes against the balance of nature.
Classified as Dark Magic
Resurrection Spells
Desiccation Spell
Transference Spell
Powers and Abilities of Dark Magic
Dark Magic possess the same capabilities as regular magic, though it appears to be slightly more potent. Unlike regular magic, dark magic is not limited by coven laws, as witches bound within circles are capable of using their dark magic without collective aid. Cassie Blake has successfully performed dark magic on several occasions while bound to her circle and was also capable of using regular magic as well, revealing witches that perform both dark magic and "white magic" appear to be able to distinguish the two apart and use them seperately.
Dark magic has been shown to penetrate an iron sulphate circle which is supposed to block a witch's magic while inside the circle. Cassie Blake was capable of setting a witch hunter on fire using her dark magic, despite the fact that she was inside the iron sulphate circle as well.
Dark Magic also appears to grant it's users a unique connection to other's minds, allowing them to view another's memories. Cassie Blake was able to see an apparition of Faye's memory while others could not with the exception of Faye. This connection was seen again when Cassie performed a spell to recall the "lost" memories of Jake Armstrong. Dark magic also appears to have a unique connection with other forms of magic (though the exact nature is unknown), as Cassie and Diana were noted to be the only witches that could form the crystal skull. Dark magic mostly appears to be an innate quality, however Royce Armstrong mentioned that John Blackwell wanted to teach the circle dark magic. Because dark magic is rooted and accessd by negative emotions (anger/hate), it's possible to some degree it can be achieved by those that do not come from dark lineage like the Blackwells, It is unknown if dark magic draws its power from other negative emotions like rage and fear, and if the more negative emotions the user has the stronger and more powerful dark magic becomes.