Troll magic is a form of magic used by Trolls and other unknown creatures like Jonas. Troll magic is very powerful, decisively more potent than the magic (that comes from the Old Religion) used by the average sorcerer.
The fact that Trolls have long been allies with the dragons indicates that even these noble creatures have respect for their mighty power. Trolls are creatures of the Earth and as such, Troll magic derives much of its power from the Earth.
However, the spells used in Troll magic are similar to the ones used in other forms of magic.
The main characteristics of Troll magic are:
- The ability to take on the form of a human through particular potions. According to Gaius, it requires powerful magic to physically change a creature like that.
- With a single deep breath, trolls can transform fine food into rotten and filthy aliments that they prefer to eat. With their breath they are capable of knocking a man out, too.
- They can cast powerful enchantments, in particular spells used to control someone's mind or heart (like love spells). Catrina enchanted a necklace using her green blood and, under its influence, Uther did anything she wanted. The only way to break this spell was to make the king cry tears of pure remorse.
- Trolls are very resistant to other creatures' magic. For example, Catrina wasn't effectively influenced by the Spell of Revelation cast by Merlin (which was powerful magic, too).
- Trolls can use magic instinctively without incantations and their power is terrible and destructive. They seem to have some control over elements (Earth in particular). For example, Catrina quickly managed to trap Merlin in the tunnels under Camelot, releasing a blast of magic power that broke a stone arch into pieces.