When manipulated by a sorcerer, the elements can be used to perform powerful magic. Generally, magic performed through the manipulation of individual elements can be counteracted with magic invoking opposing elements.
Fire is the most dangerous of all the elements. The fire spells and the heat spells are enchantments that control the element of Fire. The ability to summon a guiding light and other forms of magical sources of illumination is also related to this element.
Merlin, disguised as Old Emrys with an ageing spell, used the sword Excalibur, forged in a dragon's fiery breath, to threaten and wound the Dochraid, a creature of the earth. This indicates that, although the Dochraid believed that he couldn't kill her, the element of Fire the sword represented was more powerful than her magic (With All My Heart).
A dragon's fire can, in fact, give great power to a sword to burn, if it is begotten in its fiery breath or burnished by it. Such a weapon can kill everything, alive or dead. To save Arthur from a wraith, Merlin asked the Great Dragon Kilgharrah to burn a blade made by Gwen's father, the blacksmith Tom. The sword was later thrown by the young warlock in the depths of the Lake of Avalon, to prevent it from falling into the hands of evil (Excalibur). Excalibur was then returned to Arthur when he pulled it from the rock in which Emrys had put it (The Sword in the Stone: Part Two), after the Lady of the Lake had given it to him (The Coming of Arthur: Part Two). Merlin also used Excalibur to slain Morgana, who, because of her powers as a High Priestess, couldn't be killed by any mortal weapon (The Diamond of the Day: Part Two).
- Lyft sy þe in bǽlwylm ac forhienan se wiðere, used by Merlin to defeat the Afanc. This spell combined the elements of Fire and Wind (The Mark of Nimueh).
- Non-verbally, by Edwin, to light a candle while he was arranging his instruments for alchemy (A Remedy to Cure All Ills).
- Forbærne yfel, used by Edwin. After having thrown Gaius against a wall with a stunning spell, he conjured a circle of fire around him. The flames disappeared when Edwin was killed (A Remedy to Cure All Ills).
- Forbærnan firgenholt, used by Merlin to make a big branch fall onto a bandit (The Gates of Avalon).
- Leohtbora, used by Merlin to light a torch in the stairwell leading into the burial vault below Camelot (Excalibur).
- Cume her fyrbryne, used by Merlin when he tried to kill the Black Knight using his mortal magic, conjuring a line of fire from his feet that travelled along the ground to consume the knight. Anyway the spell failed for the wraith could only be killed by a sword begotten into the Dragon's breath (Excalibur).
- Bærne, used by Merlin to start a blaze that trapped Kanen's brigands (The Moment of Truth).
- Ástríce, used by Merlin during his magical fight with Nimueh. The young warlock cast this blast of magical energy stretching out his hand. Anyway, Nimueh was able to deflect this attack with her bare hand, being a powerful High Priestess of the Old Religion (Le Morte d'Arthur).
- Forbærne! Ácwele, used by Nimueh to send fire balls against Merlin (Le Morte d'Arthur).
- Forbearnan firgenholt, used by Merlin to make the fire in a torch grow to distract some guards. This could also be the spell Morgana accidentally enchanted in her mind that made the flame (which she also lit) of the candle in her chambers grow (The Nightmare Begins).
- Forbearnan, used by Merlin to light a fire to keep himself warm while in the woods (The Nightmare Begins). Merlin used again this spell in several occasions: as a heat spell (The Witchfinder), to block the path with a wave of fire and thus burning several of Cenred's men alive during the Great Battle for Camelot (The Tears of Uther Pendragon: Part Two) and to conjure a flame on his hand to reveal his powers to Gilli (The Sorcerer's Shadow).
- Gar onbærne, used by Merlin to set a bandit's spear on fire and thus making him fall from the tree he was hiding on (The Sins of the Father).
- Bryne, used by the young warlock to light a torch. In this episode Merlin was also able to light several candles, just by moving his hand (The Lady of the Lake).
- Hoppaþ nu swilce swá lieg fleogan, used by Merlin to make the flames of the candles he had lit fly, to amuse Freya (The Lady of the Lake).
- Wæcce on sæbát bælfýr mæst, used by Merlin to set the boat, in which he had laid Freya's body, on fire (The Lady of the Lake).
- Non-verbally, used by the jester Trickler to amaze the court spitting fire out of his mouth (without revealing his powers) (Sweet Dreams).
- Non-verbally, used by Trickler to light a candle while he was preparing a love potion (Sweet Dreams).
- The spell Morgause cast to awake the Knights of Medhir, performing necromancy, caused a great fire to erupt in the middle of the circle formed by the seven lifeless figures (The Fires of Idirsholas).
- Non-verbally, used by Morgause to conjured a column of fire to kill Arthur. This spell probably combined the powers of Fire and Wind, because a strong air current could be heard (The Castle of Fyrien).
- Miere torr sweoloþhat, used by Merlin to blow Morgause's fire wall off. The explosion caused all those who were in the room to be blasted away, and the ceiling over Morgause's and Cenred's heads collapsed (The Castle of Fyrien).
- Non-verbally, used by Morgana to set the rests of a burnt poppet, contained in a metal box, on fire. This allowed her to activate the Phoenix Eye she had given to Arthur (The Eye of the Phoenix).
- Non-verbally, by Morgause to light a torch for Morgana while telepathically calling her sister. The High Priestess cast this spell from afar, because she was in a secret room high up in the castle (Queen of Hearts).
- Intend lig, intend lig, used by Merlin, under the effect of an ageing spell, to make the fire of the pyre he was led to grow, consuming it in a massive fire ball (Queen of Hearts).
- Forbærne æltæwelice, used by Merlin to set some ropes on fire to escape from the slave trader Jarl (The Coming of Arthur: Part One).
- Bæl on bryne, used twice by Merlin to set pieces of wood on fire (The Darkest Hour).
- The curse Morgana cast upon her pendant by putting it in her fireplace caused the flames to grow higher (The Wicked Day).
- The weight spell Morgana used on Arthur's sword had the visible effect of setting, for a few seconds, the weapon's blade on fire (His Father's Son).
- Ontende þisne wyrm þæt he licgeþ unastyred a butan ende, by Dragoon. Merlin, while resting after having defeated Morgana in a magical battle, made a simple hand gesture and started a fire, in which he threw the Fomorroh while enchanting it, so that it couldn't grow again (A Servant of Two Masters).
- Ligfyr onbærne swiþe, cast by Alator of the Catha, High Priest of the Old Religion, to create a ring of fire around the altar on which Gaius was lying, so that he could perform the magical mental torture (The Secret Sharer).
- Acwence þa bælblyse, used by Gaius when he tried to resist Alator's torture. This spell allowed him to temporarily extinguish the fire (The Secret Sharer).
- Fyr wiþere, by Alator to vanquish the effects of Gaius' spell and strengthen his mental torture (The Secret Sharer).
- Scin scire, by Merlin to relight the torches that Lamia had put out with her magic, while leading the Knights to her lair (Lamia).
- Non-verbally, by Merlin to set the boat, in which he had laid Sir Lancelot's body, on fire (Lancelot du Lac).
- Bæl on bryne, cast by Merlin to block a corridor in the castle of Camelot by creating a rope of flames with the fire from to opposite torches (The Sword in the Stone: Part One).
- Bæl on bryne, used again by Merlin to set a cart he was moving towards Agravaine and his men with telekinesis on fire (The Sword in the Stone: Part One).
- The curse Merlin cast upon an effigy that represented Morgana and that blocked her magical powers caused the poppet to burn (The Sword in the Stone: Part Two).
- When Ruadan, while praying the gods of the Old Religion, realised someone was coming towards him, he used magic to blow two torches out. This spell acted as if the flames were sucked back into the wood (Arthur's Bane: Part One).
- Bæl on bryne, cast by Ruadan, after he had been mortally wounded by Sir Elyan, to shape the fire from a nearby torch into a wall so that the Knights of Camelot couldn't chase Sefa and him (Arthur's Bane: Part Two).
- Non-verbally, by Uther's ghost to set the castle's kitchens on fire in an attempt to kill Guinevere, who had been left unconscious there by the evil spirit (The Death Song of Uther Pendragon).
- Bæl on bryne, cast by Merlin to light all the torches in the armory, while he was searching for the dead king's spirit (The Death Song of Uther Pendragon).
- Morgana, while chasing a fleeing Alator through the Darkling woods, cast three times a fire spell which created a contained explosion with a cloud of fire rising from the ground. The last time Alator was hit by the blast of energy and knocked to the ground; Morgana's men arrived and captured him. The day after, Merlin, while accompanying Arthur and Gwen on a picnic, saw some scratches on a tree trunk and felt they had been caused by powerful magic: in fact, he told Gaius that in that place something horrible had happened, "something only the strongest magic could do" and that he could feel it (The Kindness of Strangers).
- Ligfyr, cast by Merlin, while hiding behind a tree, to create a wall of fire that would have prevented Mordred and the other Knights of Camelot to keep chasing him or Finna (The Kindness of Strangers).
- While Finna, a priestess of the Bendrui was running away from Camelot and its patrols, she kept casting a particular type of non-verbal fire spell on some tree trunks, leaving a burning symbol that would have allowed Emrys, who was following her, to find her (The Kindness of Strangers).
- Forþ fleoge, cast by Ari when Morgana insisted on wanting the sorcerer to give a demonstration of his powers. The spell created an air current which put out the flames in four braziers (The Diamond of the Day: Part One).
- After Morgana had used the Gean Canach to strip Ari of his magic, she forced him to humiliate himself in front of her men to make sure her enchantment had worked, threatening him that she would have killed his family if he hadn't done what she wanted, and asked him to relight the fires. Ari tried two times to cast the fire spell "Bæl on bryne", but he couldn't work magic anymore (The Diamond of the Day: Part One).
- Þurh minum gewealde ond þinum mægen... geclippaþ we þone lieg þe ealla awestaþ. This powerful spell was cast by both Morgana and Mordred, chanting it in chorus, after their army had surrounded the Camelot's garrison at Stawell. Holding each other's arm, they created a massive sphere of fire in the sky and sent it flying in the middle of the castle. As soon as it hit the ground, it exploded, releasing deadly flames which killed many men (The Diamond of the Day: Part One).
- Upastige draca, cast by Merlin in front of Arthur to reveal his powers to the dying king. The spell created a flying dragon figure in the middle of the flames, which soon disappeared (The Diamond of the Day: Part Two).
- Non-verbally, by Merlin, to light the camp fire he was setting up for Arthur. The dying king, seeing him struggling with the usual methods, gave him a look of understanding and silently asked him to show his magic (The Diamond of the Day: Part Two).
The spells that involve Wind and Air are forms of very powerful magic. Air magic is said to be as unpredictable as the winds it controls. One of the most effective is the whirlwind spell, but also other spells related to this element have been shown:
- Lyft sy þe in bǽlwylm ac forhienan se wiðere, used by Merlin to defeat the Afanc by creating a powerful air current that blew the flames of Arthur's torch into the monster, incinerating it. This enchantment combines the elements of Fire and Air (The Mark of Nimueh).
- Bene læg gesweorc, cast by the young warlock to summon the mist; this may indicate that this incantation is related to both Air and Water (The Nightmare Begins).
- Þrosm tohweorfe. Merlin cast this spell to dissipate the poisonous smoke that had been released by a trap in the Tomb of Ashkanar (Aithusa).
- Acwence þa bælblyse, cast by Gaius while he was being mentally tortured by Alator of the Catha. This spell (which can also be considered a fire spell) created an air current that allowed the physician to temporarily extinguish the flames around him (The Secret Sharer).
- The element of Air may have been involved in the spell Morgana used to strangle Merlin. The young warlock had discovered that the High Priestess had infiltrated Camelot and then Arthur's rescuing party by using an ageing spell, but before he could warn the King, Morgana stunned him and made him hit his head against a tree. She then cast a spell ("Gesweorc, hine beclyppe") on the weakened warlock to prevent him from breathing. Merlin was left unconscious and on the brink of death, but he was saved by Gaius' healing magic (Another's Sorrow).
- Færblæd wawe, used by Emrys to blow all the torches that the Knights of Camelot were using to find him in the darkness of the Courtyard out. Merlin had been framed of having poisoned the King by Guinevere, who had been brainwashed by Morgana and become her ally. He had been put in the dungeons but managed to escape with the help of his "Dragoon the Great" persona. After having reassumed his young aspect, he had been chased by the Knights in the Courtyard; by casting this spell the young warlock was able to leave everyone in the dark and climb the castle wall up to Arthur's rooms (A Lesson in Vengeance).
- Forþ fleoge, cast by the sorcerer Ari to create an air current and put out, under Morgana's command, the flames in four nearby braziers (The Diamond of the Day: Part One).
- Morgana, while taunting the powerless Merlin in the Crystal Cave, blew his torch out with a non-verbal air spell (The Diamond of the Day: Part One).
- Morgana, in an outburst of rage when her men told her they could find Arthur, cast a non-verbal spell by clenching her fist and strangled a Saxon warriors, killing him in a few seconds (The Diamond of the Day: Part Two).
- Non-verbally, by Merlin to make smoke rise in the distance, so that he could have tried to fool Morgana's warriors into believing that the men they were chasing where somewhere else (The Diamond of the Day: Part Two).
- Andslyht, used by Merlin to make the wind blow and cover his and Arthur's tracks with some leaves (The Diamond of the Day: Part Two).
Another extremely powerful application of this element is summoning a lightning. Merlin was able to master the power over life and death and did this to strike Nimueh and restore the balance of the world through her defeat (Le Morte d'Arthur). During the Battle of Camlann, both Morgana and Emrys used this lightning spell (The Diamond of the Day: Part Two).
Under an elemental aspect, stunning spells can be considered to be spells that involve the element of Air, for when they're cast, the sorcerer creates a very powerful air current that strikes his opponent.
Water is the element of purification, regeneration and of healing. The Vilia, spirits of the brooks and streams, possess healing powers and used the properties of this element to save Merlin from the Dorocha's cold and deadly touch (The Darkest Hour: Part Two).
Water is also the element of intuition, emotions and divination. One of the most important branches of scrying is hydromancy, with which sorcerers are able to See things in a water medium.
Water can be manipulated with the use of magic; there are spells that have power over this element alone or that combine it with others. An Afanc, a beast born of clay, for example, is conjured using Earth and Water, and can only be destroyed using Wind and Fire, as accomplished by Merlin and Arthur.
Nimueh, on the Isle of the Blessed summoned the power of Air and Water and gathered the clouds to rain with the spell "Tídrénas" (Le Morte d'Arthur). Merlin, when he tried free Gaius from Morgause's sleeping enchantment, created a jet of water to wake the physician up with the spell "Brimstréam" (The Fires of Idirsholas).
When Cornelius Sigan was alive, he was said to possess great control over the element of Water, as, according to Gaius, he was be able to control the tides themselves (The Curse of Cornelius Sigan). The druid Ruadan used water to perform a particular non-verbal spell: before exhling his last breath, he asked his daughter Sefa for a cup of water, in which he dipped a small white quill. He used it to write a brief message for Morgana and then, with a golden flash of his eyes, made the writing visible, just as if it had been done with black ink (Arthur's Bane: Part Two).
The spells that regard this element are used to control rocks, trees, roots or plants in general. According to Gaius, the magic that binds the Earth is delicate and can be easily undone (A Herald of the New Age).
Spells that are related to this element are:
- Eorðe, lyft, fyr, wæter, hiersumaþ me. Eorðe ac stanas hiersumaþ me. Ic can stanas tobrytan. Hiersumaþ me, used by the High Priestess Nimueh to control the Earth in order to make the rock on which Arthur was standing collapse. Considering the translation of this enchantment (Earth, air, fire, water, obey me. Earth and stones, obey me. I have the knowledge to break the stones into pieces. Obey me), it's interesting to notice how Nimueh was at first invoking all the elements and then focused her attention on the rocks and stones (The Poisoned Chalice).
- Gehæftan, chanted by Anhora when he had some roots of the Labyrinth of Gedref tie Merlin up (The Labyrinth of Gedref).
- Ic ábíetee þæt stánhol, by Merlin when he tried to break the stones of the prison in which Catrina had trapped him. The troll was able to command magic of such power that even Merlin spent the entire night trying to make his own powers prevail on Catrina's (Beauty and the Beast: Part One).
- Blóstmá, cast by Emrys to create a flower and offer it to Freya (The Lady of the Lake).
- Non-verbally, by Merlin to magically make a branch grow and trip Mordred, as he was running away (The Witch's Quickening).
- Ic þe bebiede þæt þu abifest nu, by Merlin to make the ground shake, creating an earthquake. The sorcerer performed this spell, reciting its words and then hitting the rocky floor of the ancient tomb of King Lothar with his palms, to prevent Odin from chopping Arthur's head off and to save him, along with Mithian and King Rodor from Morgana's clutches (Another's Sorrow).
- Wanne nædran, fram þæs foldan bosme astigaþ ge. With this spell, Morgana enchanted the ground itself and created a faint mist. Out of it ("from the womb of the earth", as the spell says) rose two magical and poisonous snakes that attacked the Knights of Camelot. These creatures were made of dark magic, just like the poison they injected into Leon's and Percival's veins. Thanks to the magical substance coursing with their blood, the sorceress was able to implant horrible visions of the Dark Tower into Leon's and Percival's minds (The Dark Tower).
- A possible spell related to plants had been cast by Morgana to grow a brown vine along a tree trunk in the woods outside Camelot, possibly to indicate the place where she was going to meet Guinevere. When Merlin and Gaius went to the woods in search of some evidence, the young warlock noticed the vine and Gaius said "It's certainly not natural" at which Merlin replied "It was Morgana, I'm sure of it" (A Lesson in Vengeance).
- After having seriously been wounded by the fiery power of Excalibur, the Dochraid, a creature of the earth, cast a spell in her cave to take strength and energy from the rocks and the ground, curing herself. With a fierce and wicked tone of voice, she chanted these words while leaning against a rock: "Ge hæle þisne lichaman. Gestrenge me nu þæt ic beo swiþe mihtig hie to forwiernan; yfel is on ofost!" (With All My Heart).
- Stanas ahreosaþ, cast by Morgana to cause a rock fall and trap Merlin, who had been stripped of his magic, in the Crystal Cave, creating an impenetrable wall of stones (The Diamond of the Day: Part One).
- (Apparently) non-verbally by Merlin, in his aged form, to blow Morgana's magical wall up and free the passage out of the Crystal Cave (The Diamond of the Day: Part One).
Some spells used by the young warlock to make the ceiling collapse on the Knights of Medhir (The Fires of Idirsholas, "Ahríes þæc!"), on Morgana (The Tears of Uther Pendragon: Part Two, "Feoll bu brand"), or on Lamia (Lamia, "Feall hushefen") could be other incantations that control the element of Earth.
Merlin once more displayed his powerful magic when he controlled this element again and caused, with the incantation "Gewican ge stanas", some rocks to fall, blocking the path between King Arthur and a group of bandits in the Valley of the Fallen Kings (A Servant of Two Masters).