Magic in the Magica Universe are forces created from fluctuation of emotion, unbounded by the First Law of Thermodynamic. When Kyubey's scientifically-advanced race discovered magic, they realized its capacity to create new energy can postpone maximum Entropy and delay the heat death of the Universe. However, Kyubey's race is incapable of emotions, thus they scoured the Universe for species with the most emotional potential. He found his answer in Earth's human females, especially those still developing secondary sex characteristics. Magical girls and Witches, and thus the settings of the story, are the result of Kyubey's quest to harvest this energy.
Three types of magical creatures exist in Magica universe: magical girls, witches, and familiars. However, because both familiars and magical girls can mature into witches, all three may be considered stages of a single species. Souls of magical girls and witches are separated from their bodies and reside in soul gems and grief seeds respectively. Because of this, magical girls and witches are highly invulnerable as long as their soul gems or grief seeds are intact and can recover in due time. Familiars do not have grief seeds so they are presumed dead when killed. Both soul gems and grief seeds are adorned by the emblem of the holder, and familiars carry the emblem of the witch from whom they budded from.
Read more about emblems at soul gems and grief seeds.
These are magical abilities common to all magical girls. For magical girls, magic usage (inside and outside of battle) causes their soul gems to become tainted, which must be cleansed by a vanquished witch's grief seed. With training, magical girls can become more proficient at these abilities and reduce magic usage. According to a magazine article, veteran magical girls will become very powerful in time as they gain experience. They can also develop different magical powers beyond those of their original abilities:
- Summon weaponry: Magical girls typically summon their offensive weapon from thin air or their soul gem at will. Each has their own characteristic weaponry and fighting style that they gain increasing proficiency at. Mami and Sayaka at least are able to make as many of them as they desire, and the weapons are not necessarily mundane as Mami's rifles fire blasts of magic, not bullets. For a catalogue of weapons used in the series, see Weapons.
- Henshin: Magical girls undergo a magical transformation that summons a fancy new costume onto their body. It is assumed that the costume provides protection.
- Physical enhancements: All magical girls exhibit superhuman strength, agility, reaction, and regeneration. Further training allows the girls to be able to shut off their sense of pain during battle. They are also capable of harnessing the regenerative power to heal problems like nearsightedness. According to Kyubey, it is possible to keep fighting even with every drop of blood in their body drained by healing it with magic. These physical enhancements also include the ability to jump to incredible heights.
- Witch Detection: Soul gems glow when there are witches nearby, or if there has been witches nearby recently. From Episode 1, when Mami tells Homura that she can still chase after the witch, and from Episode 6, when Sayaka tries to find the trail of the familiar Anja, witches seem to leave behind some sort of trail of energy which magical girls can detect and follow. From episode 9, when Kyoko assures Madoka that the witch she's chasing has the same energy signature, it can be surmised that each witch has a different trail, possibly similar to a fingerprint or other identifier. In essence, every witch may be unique. It is unclear whether a witch's familiar has the same energy signature as the original witch, and it is unclear whether soul gems can also detect victims of a witches' kiss.
- Telepathy: Magical Girls are able to use telepathy to communicate with other people, including normal humans. However it is possible there is a limited range on this ability or that Kyubey is needed to act as a relay. Only Mami and Kyoko have displayed the ability to do it without Kyubey thus far.
- Flying/Hovering: While so far only Homura has displayed the outright ability to hover in the air (during her fight with Walpurgis) it's not impossible they can all learn to do it.
While magical girls who aren't transformed are unable to use their magic, they still use up a bit of it to sustain their body involuntarily in their daily lives. However, even without transforming they can still use their Soul Gems in a limited fashion to perform magic. For example, the Soul Gem can be used:
- To summon a magical weapon still attached to the Soul Gem.
- To heal eyesight (and it is assumed any form of injuries in the body).
- Adjust a body's ability.
- Preserve a dead body from decomposition.
- Magical arrows: Madoka can produce arrows of pink magic that seem to explode on impact. She can fire as many as five in one shot and they appear to be able to curve in mid-flight to change direction.
- Incredible potential: Madoka is able to take out Walpurgis in one hit in the right conditions. This would appear to burn through her magic near instantly however, and turn her into a witch.
- Regeneration: Sayaka can quickly regenerate any otherwise fatal body damages and continue fighting. Because of her wish relating to healing someone, she uses less magic to do this and is more efficient at it than other magical girls like Mami.
- Screen sweep: Leaving blue streaks in her wake, Sayaka is able to quickly bounce across the entire battlefield and take out any enemies in her path.
- Time stop: Homura can temporarily stop time in the surrounding area with exception of herself and anything in direct contact with her (such as holding hands).
- Hammer space: Besides blocking damage, her clockwork shield can store any size and amount of munition. Thus far, Homura has seen storing and pulling out from it pistols, grenades, flashbangs, an M249 and a large amounts of RPGs.
- Energy manipulation: She would appear to be able to fire purple-ish blasts of magic out of her hand (or Soul Gem), as well as form energy barriers around her shield to block attacks. In chapter 5 of Oriko Magica she creates a defensive barrier around Madoka.
- Time loop: Homura can rewind time back one month; however, she must wait at least one month between uses (or use up one month's worth of sand in her timer).
- Healing: Homura is seen healing her eyesight, allowing her to no longer wear glasses. It's also possible that she altered her physical state, allowing her to beat the school's pole jump record.
- Healing: In episode 1, Mami demonstrated the ability to heal wounds on others. Unlike Sayaka however, whose wish was related to healing, Mami is not as good at healing quickly like Sayaka can.
- Restrain: Mami can summon ribbons to restrain and incapacitate an adversary.
- Ribbons: She can shape her ribbons as she sees fit, making bridges or giant pistols out of them. Mami had to study the mechanics of pistols first before being able to shape her primary weapon (ribbons) into them though.
- Other abilities: Mami placed a ribbon barrier around Madoka and Sayaka in episode 1 to protect them from harm, and imbue Sayaka's bat with magic in episode 2. It is unknown if these abilities are learned or unique to Mami.
- Erecting fencing: Kyoko can erect a impenetrable, latticed barrier to keep others from harm or to isolate her adversary.
- Giant spears: Said barrier is made of giant spears. She would appear to be able to ride them and they behave somewhat like snakes due to their chained nature.
- Create Duplicates: This attack was shown in Drama CD 3, "Farewell Story", where she created up to 13 duplicates of herself. The attack was named Rosso Fantasma by Mami. Kyoko's subconscious mind blocks her use of this power after she lost her family.
- Energy manipulation: Kyoko is also able to shroud herself in a powerful magical glow. Whether it has any effect or is just for show remains to be seen.
- Soul Gem detonation: Suicide attack. Able to take out witches in one hit. It is unknown if other magical girls can also do this at will.
- Other abilities: Kyoko was able to keep Sayaka's (soulless) body from decaying while also keeping it warm. This might be a generic use of magic all of the girls can learn to do, but it might also just be an application of healing magic on a body other than hers.
Witches and familiars reside in magical labyrinths of another dimension. These labyrinths interface with the real world at specific locations through an unknown mechanism, but can be entered by magic girls through ripping open barriers. To attract normal people to their locations to feed upon, witches infest unhappy people with a witch's kiss, which either attract them to these locations to commit suicide (if unhindered) or kill them off with diseases. For this reason, witches tend to gather around violence-prone areas and hospitals.
The labyrinths consist both of elements from their locations in reality and of allusions to the witches that create them. Deeper within the labyrinth, more references to the witch will be seen and fewer elements from reality show up. For example, in Episode 1, the labyrinth is set in a floor waiting for refurbishing, and it was fulfilled with 'under construction' signs and barriers of a construction site. In episode two, the labyrinth is set in an abandoned concrete building, thus the rooms in the labyrinth are made of solid concrete, making its appearance differ from Episode 1 even though the owner is the same. As the protagonists approach the the final room, elements of a rose garden start to dominate the construction elements. In episode three, the labyrinth is set in a hospital, therefore surgery signs, needles, gallipots, and wards are presented first, but deeper in, those are replaced by various kinds of desserts. The barrier can also be influenced by the strong emotions of the people within them, as seen in Episode 3 when Mami and Madoka make their promise.