The Noir Fuel Spirit Devices are small magitronic devices created by Croix in order to absorb emotional energy and convert it into magical power.


These devices are small and very numerous cubes that have a different color depending on the type of emotional energy they find absorbed (Red: anger - yellow: joy - blue: sadness - purple: hate - turquoise: fear - green: anxiety).

Being close to strong emotional energy, these devices are able to absorb it and turn it into powerful magical energy. Depending on how much emotional energy they have, they will produce greater magical power. According to Croix's research, anger is the emotion that produces the most power.

When these artifacts are reunited, they are able to transform into different creatures under the control of Croix, including trolls, bird monsters, reptile beast and giant spider. They also show that they are able to enter into an object in order to manipulate it. Notable monster form that they had are:

  • Goblin Form: Posing as fake goblin during the faerie strike.
  • Snake Form: For combating Ursula. Used during events of "Wagandea".
  • Reptile Beast Form: To acquire samples of Dream Fuel Spirit and combat.
  • Spider Form: To attack and restrain Akko. This form has a unique ability to fire restraining webs.
  • Crow Form: For harassing civilians and attacking Sucy, Lotte, Amanda, and Jasminka during the Wild Hunt.