This form of magic involves time. Gifted magical creatures can slow down objects or, under certain circumstances, time itself. It's unknown if this powerful skill requires non-verbal spells incanted in the sorcerer's mind or is just a power that magic practicers use instinctively, changing the reality around them by harnessing the power of the world to their own. This kind of magic is rare and very difficult to use and only the most powerful creatures of the Old Religion can achieve it. Merlin has shown countless times to be very skilled with this ability and has incredible reaction time, being able to dodge and duck out of the way of things at the last minute.
Time magic is also mastered by the Crystal of Neahtid and the other crystals of the Crystal Cave. They are powerful magical instruments that hold the secret of time itself along with great knowledge: knowledge of what is, what has been and what is yet to come.
This form of magic has been used the following times:
- By Merlin
- To save Gaius from a deadly fall by slowing down the physician's body (The Dragon's Call).
- To slow down a bucket of water when Gaius accidentally spilt it (The Dragon's Call).
- To decelerate the movement of Mary Collins' dagger before it hit Arthur, allowing him to save the Prince's life for the first time (The Dragon's Call).
- To slow down and then stop the axe that Edwin Muirden had sent against him with telekinesis during their magical duel (A Remedy to Cure All Ills).
- To slow down time itself so that he could observe the Sidhe, who keep their true form hidden to normal eyes, appearing only as a glowing sphere, by moving incredibly fast, as Aulfric of Tir-Mor spoke to them. In this occasion Merlin showed his very powerful magic, because he was able to slow the time all around him, including the reeds on the shores of the Lake of Avalon, the branches of the trees moved by the wind and the waves on the surface of the water (The Gates of Avalon).
- To slow down the Sidhe elder's movements, who appeared as a blue floatins sphere of light, while fighting him, allowing him to kill him with his Sidhe staff (The Changeling).
- To inhumanly, through the type of magic, perceive the otherwise nearly instantaneous movement of a dagger to see if it was going to hit Arthur. (The Wicked Day)
- By other creatures of magic:
- By Morgause who, with her spell that summoned Ygraine's spirit from the dead, opened the doorway (likely the Veil) and stopped the time all around her, allowing Arthur to talk to his deceased mother. The spell didn't hold long and the doorway was quickly closed with the time going on again at its normal speed (The Sins of the Father).
- By Grunhilda to slow down the Sidhe's movements and talk to the Sidhe elder (The Changeling).