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Null Magic (無属性魔法,Muzokuseimahō?, literally meaning "no attribute magic") is one of elemental magic exists in In Another World With My Smartphone series. This type of magic is exclusive for magician with Null (無属性,Muzokusei?) affinity and this attribute does not fit with the other six attribute.
Null magic can be regarded as personal magic as only the person who has the spell can use it. As mentioned, it is infrequent for two people can use the same spell but it is also possible for a spell has similar effect with one another. There are various magic spell which are being classified as null magic. The number of the spell is very huge which made the null magic book looks like a phone book rather than a magic book. The spells, that are being recorded, are spreading from minutiae spell like, spell for lengthening the time of smoke of an incense stick, spell for making the color of tea more vivid, and spell for smoothing off the splinters from wood, to profound spell like 【Program】 which allowed the users to give a set of instructions or rules on an object or 【Analyse】 which allowed the users to browse the mechanism of an object or 【Delete】 which allowed the users to erase the existence of an object. Because of the nature of the magic, null magic books are often sold as entertainment purpose rather than as study book.
The outcome of the spell is correlated with the physical or magical power of the user. It can be seen when Touya lost when competing with Elze on carrying competition using 【Boost】.
It is almost impossible for a human can use more than 2 null magic spell. The fairy clan has higher aptitude toward null attribute which is why it is common for a fairy to have null magic.
Any magicians need to have affinity toward null attribute before they can use null magic. For testing one's aptitude with certain attribute, magic stone can be used. Normally, the magic stone amplifies and releases the user's magic power into certain element that the stone represents, however null magic stone only amplifies the user's magic power without releasing any elemental substances. The magic stone for null attribute is colorless. Unlike other element, null magic has no element summoning spell, so for testing their null attribute, magicians need to know their personal null spell beforehand while holding a magic stone, and if the magic stone reacts, then the person has an aptitude for that attribute.
Unlike other attribute, null magic has different mechanic regarding its incantation. To activate a null magic spell, the users must concentrate their magic power then chant the null magic name. Because of the specificity of each null magic, some spell might requires additional prerequisite. For example, 【Aports】 can only be used for object with certain size. On certain occasion, when the users have more than one null magic spell, they can combine their spell into one spell. The combination of null magic spell can be seen when Touya Mochizuki used 【Enchant:Reading】 on a glasses.