The Nefarious Codex lexicon is shaped like a rectangle with curved corners. Its border is yellow and it is lined by black spikes, five on each cover. The spine is decorated by a white cross that resembles the upper half of the Nobody logo. Its side arms are longer than the other two, and they extend onto the covers. The rest of the lexicon is blue with a thin, black outline.
"Nefarious" means "infamous" or "evil". A codex can refer to the modern book binding format of joining pages, as opposed to rolling a scroll. A reprint is a written material that has been published more than once.
Nefarious Codex's ground combo begins with a leftward/rightward swipe, followed by a second leftward/rightward swipe. At this point, a spear-like weapon extends from the lexicon's pages, slashing from top right to bottom left, then from top left to bottom right, back from bottom right to top left, then a final thrust forward as the finisher. If is pressed, the book expands and the spear appears with a forward thrust.
Nefarious Codex's aerial combo is very short, consisting solely of a downward slash, an upward slash, and a spinning forward throw.
When Nefarious Codex makes contact with an enemy, a periwinkle star-burst appears along with a burst of purple and white diamonds.
| Terminus | Bahamut | Crux | Absolute Zero | Megacosm | Nefarious Codex | Astrologia | Blaze of Glory | Da Capo | The World | Mournful Cineraria | Étoile | Crown of Guilt|
Soul Eater | Mage's Staff | Knight's Shield | Kingdom Key D | Kingdom Key