Voodoo

Voodoo (ブードゥ) is an African diaspora religion, a mishmash of Afro-Caribbean witchcraft and necromancy.

Principles
There are a number of spirits or deities within Voodoo, referred to as the (also spelled lwa). One of these figures,, serves as intermediary between his kind and humanity, and thus indirectly appears in all Voodoo ceremonies.

There are a number of concepts which are associated with Voodoo, some originating from cultures where Voodoo is also present, but are technically the result of misconceptions or falsities. Despite this, these concepts and their associations can be put into practice regardless.

Background
Voodoo has its roots in traditions and religions from West Africa. These beliefs were brought over to the with the slave trade, where they became syncretized with the culture of the slave owners together with a little Native American influence, eventually producing several varieties of the religion which came to be known as Voodoo.

Voodoo was present in the during the age in which  terrorized the seas.

Shinyaku Toaru Majutsu no Index
A member of the true Gremlin, Zombie, has a background rooted in Voodoo as well as actively drawing in a great number of cultures, giving her an affinity for almost anything which allowed her to devise a spell which would allow the Magic Gods to safely enter the world after their Hidden World was breached. Toyama Luca of the Kamisato Faction also makes use of Voodoo-based magic as a follower of Legba Atibon.

Uses of Voodoo and associated concepts in the story

 * Legba Atibon: A loa who serves as the intermediary between the loa and humanity, standing at a spiritual crossroads, and a facilitator of communication, speech and understanding, believed to speak all human languages.
 * Luca follows Legba Atibon and makes use of his role as a deity who manages ceremonies (indirectly appearing in all Voodoo ceremonies through his role as intermediary), therefore not just existing on a specific ceremonial day but at all times, to achieve control of subjective time, allowing her to change the age of her external appearance and prepare magic normally once-in-a-decade in seconds.
 * Sacrificial Rituals: There are some pacts associated with Voodoo which involve a person selling their soul to gain power and require them to regularly sacrifice others, otherwise they pay with their own life. These sacrifices can't just be anyone and have to be people whom it pains them to sacrifice, such as family members or lovers.
 * Salome refers to Voodoo practitioners who, having sold their soul, must annually sacrifice someone dear to them or forfeit their own life, when describing her own sacrificial magic and what she has sacrificed.
 * Lucia referred to this type of sacrifice during her, Agnese Sanctis and Angelene's investigation of the magical forensic cleaning at Nihili Padpois's restaurant.
 * Ti Bon Ange: A dualistic aspect of the soul in Haitian Voodoo traditions, which is responsible for an individual's identity and personal characteristics, while the Gros Bon Ange is responsible for biological functions.
 * One of Isabella Theism's spells, which involved the use of zombie powder, has a command which includes the Ti Bon Ange.
 * Voodoo Dolls: Effigies which represent a person, sometimes with a piece of them attached, and used to manipulate or bring harm upon them.
 * The Lotus Wand's method of causing attacks based on effects occurring to the wand is noted to be similar to the ones used on voodoo dolls.


 * Zombie: Originating from Haitian culture and associated with Voodoo, a dead person reanimated as an undead or a person placed into a death-like trance, through magic, to serve as a slave.
 * A Magic God of the true Gremlin is known as Zombie and has a background in Voodoo.