Avalon Spell Book 10 (2016)

From publisher blurb:

Avalon takes a common spell and provides you with a number of alterations and additions to add excitement and useful options for your next adventure. Each issue of Avalon Spell Books will focus on a new spell, discussing different versions of the spell, providing different components that can be used to alter the way the spell works, and even adding feats and new magical items linked to the spell in question.

Magic aura spell has long been part of cheating trader's repertoire, a safety measure in the areas where magic is restricted, or an occasional way to set an attractive decoy. Primarily ignored by adventurers, it is a potentially valuable asset to a dungeon keeper or any spellcaster who already has a dwelling protected by magic.

To make the spell really worth casting, one needs to consider two tricks with the aura-changing mechanics that are not automatically available with this spell. The first trick is adding it as a permanent effect to a magical item - or even better, to a magical trap, - which is really a way to deal with those intruders who routinely check everything with the cheap detect magic 0-level spell before making a step forward. The second path of improvement requires increasing the spell's area to affect larger objects and even places, potentially masking overland enchantments and multiple minor magics within. Both additional ways of using magic auras are covered in the text below.

Finally, being able to alter the ways your spells are perceived by other creatures can grow into a full-scale illusionist technique, based on manipulating auras of existing spells. AS an example of such techniques, a new focused arcane school of aura shaping is presented here, with some new aura-related powers.