Mystiokinesis

"But magic is neither good nor evil. It is a tool, like a knife. Is a knife evil?  Only if the wielder is evil."

- Hecate

Mystiokinesis, or reality warping, is the ability to cast and manipulate magic, for example: creating snow, changing the weather, turning other people into animals, etc. Thus, giving it control over everything and everyone. Magic is a very complex and dangerous force as it gives control of natural energies in order to produce a needed positive change, but also could be used for evil purposes. Hecate and her children are especially skilled at this form of manipulation.

The Sea of Monsters
When Annabeth and Percy washed up on C.C.'s Spa and Resort (run by Circe, a daughter of Hecate, the Goddess of Magic, and Helios, the Titan of the Sun) Circe turned Percy into a guinea pig, along with several other people (including the pirate Blackbeard and his crew), using her potion. She offers Annabeth the chance to stay on the island and become an immortal sorceress like herself. Annabeth ultimately declined. Annabeth then gives Percy, the guinea pig, and the other transformed humans some of Hermes' multivitamins, returning them to their normal selves.

The Last Olympian
Hecate associated herself with the Titans during the final battle of The Second Titan War. To prepare the battleground, she cast a spell around all of Manhattan to put millions of mortals to sleep and decelerate time which, together with Morpheus' ability, prevented mortals from entering the place of battle. Hecate also tried to break through the wards of Olympus, but failed as the wards on Olympus were too powerful.

The Lost Hero
During Medea's fight with Jason Grace, Leo Valdez, and Piper McLean, she showed her magical abilities, as well as boasted about how Circe taught her magic. During a meeting of all the cabin counselors, Lou Ellen magically removed Miranda Gardiner's nose from her face, and Miranda was trying to get it back. She failed until Chiron told Lou Ellen to give Miranda her nose back.

The Mark of Athena
Annabeth mentioned that the campers of Hecate's cabin used their magic to try and find Percy at Camp Jupiter and were unable to.

Son of Magic
Lamia and Alabaster C. Torrington both showed a high level of skill in this power as Alabaster was mentioned to be the most powerful demigod child of Hecate. They fought each other with incantations, and Alabaster was, at the end, about to destroy Lamia with a spell before Hecate separated them, not wanting her children to kill each other. Finally, Howard Claymore was returned to the world as a Mistform after he died, by Hecate. Lamia mentioned having crafted a spell that gave monsters the ability to sense and track demigods. Claymore stated that if you put enough power behind an incantation, it can come true. Hecate stated it takes magical energy to cast magic.

The House of Hades
Hecate used the Mist to form three blurred, smoky images of the same woman moving in unison. Whenever Hecate is present, a swirling column of Mist surrounds her. She also manipulated the Mist to make Hecuba look like a black cat. Hazel Levesque learned from Hecate that she has the ability to manipulate the Mist to a strong degree. Hazel spends most of the book learning to use Mystiokinesis. The first time she successfully uses it is when she and Jason defeated Sciron. She then used it against Pasiphaë, manipulating the magic of the Labyrinth so she and Leo could defeat her.

The Blood of Olympus
Hazel used the Mist to disguise Jason, Annabeth, and Piper McLean while spying on Gaea's ghosts in Ithaca, and again to disguise Percy, Piper, and Annabeth as Earthborns to sabotage the Giants. Hylla mentioned that some of her followers are Amazons and it was easy for them to pull Nico di Angelo, Reyna, and Coach Hedge off course stating that Shadow Travel is magic. Lou Ellen and the half-bloods of the Hecate Cabin protected Camp Half-Blood with magic barriers to slow the impending Roman invasion. Lou Ellen Blackstone uses the Mist to hide the four demigods from the Romans so they can complete the task without getting spotted.

The Dark Prophecy
Apollo mentioned that the Triumvirate Holdings managed to sabotage all forms of communication used by demigods, including the arcane magic version of email. Josephine mentioned that Magical construction is her specialty. Josephine began to teach Calypso how to get her magic back and regain control over her magic.

The Burning Maze
Medea used her magic to summon Helios from Tartarus. She also attacked the trio with gusts of wind. She drained Helios's godly powers to combine Apollo's last immortal essence and Helios's to make Caligula a god.

Known Spells
The amount of different spells is unlimited; ranging from anything small to giant. Most of the spells (as seen used by Lamia and Alabaster C. Torrington) begins with a Latin word "Incantare" which means "To Enchant".
 * Unnamed Time Deceleration Spell - A powerful spell that decelerates the flow of time. The spell repelled any mortal who attempted to enter it, as cars were seen veering away from the Manhattan exits like they were getting a subconscious message to turn back. It was cast by Hecate to prepare the battleground for the Second Titan War.
 * Unnamed Sleep Spell - A huge spell that can sleep millions of mortals in a location. This spell also creates a barrier around the location, causing any mortal who passes it, or who was already within it, to fall instantly asleep. The spell is slow-acting. This spell was cast by Hecate on Manhattan in order to prepare the battleground for the Second Titan War.
 * Unnamed Ward Breaking Spell - A spell to break through magical wards. This spell manifests as blue lights streaking across the sky towards the target location like tiny comets. If the wards are too powerful, the blue lights fizzle out as soon as they come too close to the wards. This spell was cast by Hecate to try to break through the magical wards of Olympus but failed to do so as the wards were too powerful.
 * Magia Occultandi (Enchantment of Hiding) - A concealment spell that shields oneself or others from the tracking abilities of monsters.
 * Gelu Semita (Path of Frost) - A cold-based spell that generates cold. It is a type of translocational spell, which allows the caster to make a path for themselves and ice is the method of travel which allows them to obscure their location, making it hard for their attacker to attack or anticipate their next attack. It also makes the temperature drop thirty degrees and get colder and hail starts to fall.
 * Templum Incendere (Temple of Fire) - A fire-based spell that is set to destroy the person's "sanctuary", whatever the target places the most faith in. This spell does not affect the target personally. The spell makes the temperatures spike and feel like a sauna as the heat keeps building and things begin to be set on fire.
 * Stulti Carcer (Fool's Prison) - A spell that makes a person's legs feel like lead and glued in place. This spell was cast by Lamia to stop Dr. Howard Claymore from saving his friend Burly Black.
 * Unnamed Protection Spell - A spell to protect oneself or others from harm. This spell can even be used to protect the user from death. Alabaster cast this spell on himself and survived the explosion of the Princess Andromeda in The Last Olympian.
 * Unnamed Magic Disruption Spell - A spell that disrupts a person's magic and spell insignias. It was cast by Lamia on Dr. Howard Claymore so that the spell would disrupt Alabaster's magic and spell insignias.
 * Aufero Sarcina (Remove Package) - A counter-spell to remove another caster's enchantment from themselves or another person. It used by Alabaster to remove all of Lamia's enchantment from Howard Claymore. Once cast, it causes an explosion and green shards of light to fly from the person, making them stagger backwards.
 * Persequor Vestigium (Following Markings) - A spell that presumably locates another person. Once cast, the caster is surrounded with a collage of magical spells and it radiates their entire body with power. It was cast by Alabaster to find Lamia. The spell also made the symbols on his sword blaze even more fiercely and every rune on his clothes shone like miniature spotlights.
 * Unnamed Binding Spell -  A very advanced spell that allows the user to imprison a target and bind it in a pile of black soil for eternity, which could prevent monsters from reforming. The spell requires a lot of energy from the caster. This spell is the reversal of Healing Spells. This spell is a shorthand incantation.
 * Unnamed Monster Sensing Spell - A very advanced spell that allowed all the monsters in the world to sense demigods. This spell was crafted by Lamia.
 * Healing Spells - Spells to heal and fortify a living body. Healing Spells are the reversal of the the Binding Spell.
 * Unnamed Separation Spell - A very advanced spell to separate two or more people using powerful magical energy. This spell was cast by Hecate to separate Alabaster and Lamia so neither one of her children died.
 * Unnamed Mistform Body Spell - A very advanced spell that gives a spirit a Mistform body. This spell requires a lot of energy from the caster and would take most of the caster's power.
 * Unnamed Pluto Summoning Spell - A spell to summon the god Pluto. This spell was cast by Marie Levesque to summon the god Pluto.
 * Unnamed Magic Barriers Spell - A spell to protect a location with magic barriers to keep danger out.  This spell was cast by Lou Ellen Blackstone and the half-bloods of Hecate's Cabin.
 * Unnamed Weapon Transformation Spell - A spell to turn anything into a weapon. This spell was taught to Alex Fierro by his father Loki.
 * Unnamed Chlorokinesis Spell - A spell to control and manipulate plants. This spell was cast by Medea to cause the enchanted trees to stop attacking Jason.
 * Unnamed God From Tartarus Summoning Spell - A powerful spell to summon a god from Tartarus. This spell was used by Medea to summon Helios from Tartarus.
 * Unnamed Godly Powers Draining Spell - A powerful spell to drain a god of their powers. This spell was used by Medea to drain Helios' powers into another person to elevate their powers and make them a god.

Known Potions

 * Circe's Potion - A potion that transforms a human, usually a male, into a guinea pig. This potion was described to taste like a strawberry milk shake.
 * Medea's Sunscreen - A potion that makes a person resistant to certain types of fires and getting burned.
 * Disease Healing Potion - A potion that will heal any disease, possibly even lost memories. This potion is bloodred in color.
 * Unnamed Killing Potion - A potion that will kill a person very painfully. This potion is blue in color.
 * Unnamed Blindness Potion - A potion that induces blindness.
 * Unnamed Insanity Potion - A potion that induces insanity.
 * Unnamed Sleep Potion - A potion that induces sleep.
 * Unnamed Memory Forgetting Potion - A potion to make a person forget certain memories.
 * Healing Potions - Potions that can heal injuries and wounds. Most healing potions don't taste good and taste like pond scum soup.
 * Medea's Magic Paste

Weaknesses
Magic requires energy and it takes it from anywhere it can get it, including the user's own magical energy. If a user overexerts their magical capabilities too much, it physically takes a toll on their body causing them fatigue, exhaustion, dizziness, or fainting. It could also cause their magical energy to be drained or depleted, leaving them unable to use their magic until it recharges, leaving them defenseless. If a user isn't powerful enough and don't know how to cast them effectively, they will be unable to cast incredibly powerful spells.

Trivia

 * Magic has a way of turning on the user.
 * In The Last Olympian, Silena stated that the bigger the spell, the easier it is to resist.
 * In The Demigod Diaries, The Son of Magic, Dr. Howard Claymore stated that incantations are a simple concept; if you say something with enough power behind it, it can come true.
 * Despite Templum Incendere being translated as Temple of Fire, the literal translation of the phrase means set fire to the temple.
 * According to Hecate, magic cannot create something out of nothing, it makes use of what already exists.
 * According to Hecate, it takes energy to cast magic.
 * According to Hecate, a noble sacrifice creates powerful magical energy.
 * Mystiokinesis is one of the most versatile powers displayed in the series as it has the potential to replicate the effects of other abilities such as pyrokinesis and atmokinesis.
 * As shown with Hazel Levesque, demigod children of witches possess magic.
 * According to Hylla Ramírez-Arellano, Shadow Travel is magic.
 * According to Hylla, if another person teleports themselves or others, it is easy to pull them off course, especially if the teleporter or another person being teleported share a connection.
 * According to Pluto, the secret to all magic is making the target see what they want to see.
 * Hecate and her demigod children's magic are strongest at night and weak during the day.
 * According to Setne, when doing hybrid Greek-Egyptian magic, a little demigod blood is a great catalyst.
 * According to Britomartis, magic is tricky stuff and you never know when or how it's going to come out.
 * According to Calypso, half of magic is acting like it will work and picking a superstitious mark.
 * According to Apollo, magic to destroy a god is entirely possible if they are powerful enough, provided their victims are weak enough to be overcome.
 * A powerful enough magic user can bring back a god from Tartarus and even make a mortal a god.