Dark Regulus is an anime-only Caster Magic.
Dark Regulus, much like its light-based counterpart Regulus, is a Magic that allows its user to imbue their body parts with the Magic itself for melee combat, however in this case the Magic manifests itself as dark flames. The Magic can also be used for ranged combat, with the user being able to shoot the dark flames from their palm to attack from afar. Moreover, Dark Regulus has shown the capability to absorb "light", such as other types of fire, in order to nullify their foe's attacks while using the absorbed Magic for themselves. Additionally, whilst Dark Regulus appears to be unlimited in the amount of flames the user can absorb, there actually is a limit, however the more light that there is to absorb, the longer it lasts and the stronger it becomes. The Magic also appears to be critical for the successful performance of Liberum, as it was used to ignite the Celestial Globe, which then started the entire process.
- Hammer of Darkness:The user covers their fist in the flames of Dark Regulus and uses it to punch their target.
- 'Sanction of Darkness': The user quickly moves to appear in front of their target and engulfs them with the dark flames, dispelling their Magic if they are using any, as well as dealing damage.
- Roar of Darkness: The user shoots out dark flames from their mouth and sends them towards their target. This spell was strong enough to overpower Natsu Dragneel's Fire Dragon's Roar.
- Exploding Flame Blade of Darkness: Using Dark Regulus, the user sets both of their fists aflame and rushes at their opponent, delivering a barrage of attacks. After absorbing the flames of Dark Regulus, a Fire Dragon Slayer can also use this spell to blast away their opponent by combining their own flames with the dark ones.
- Purge of Darkness: The user releases a stream of flames from their palm and directs it at their target, pushing them back while dealing damage.