Time Traveling Theory for Idiots (La Teoria dei Mutamenti Temporali in the original Italian) is a treatise of which Magica De Spell owns a copy.
A heavy purple gold-bound spellbook, Time-Traveling Theory for Idiots is a treatise on time travel, specifically dealing with temporal mutability — the circumstances and side-effects of altering the timeline. For example, it documents that when using the Time-Tuner Vortex Spell, one should avoid interacting with the visited period of the past at all costs, at the risk of causing unpredictable changes to the present.
Behind the scenesEdit
Time-Traveling Theory for Idiots appears in the 2007 story The Time Vortex.