For information, the term ¨Faiel" is a Mistranslation of "Fire".
When he shoots he says "FAIERU", that's how the author wrote "Fire" in Katakana.
Faiel is not the name of anything, it's just "Fire", if he shoots a gun or a cannon, he says the same thing
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And for those who may ask "Where did he get the gun from, and how does it work?"
- Create the base with "solidified Demon King blood".
- Insert an Orichalcum bullet.
- Use a shit ton of Mana for telekinesis on the bullet to "throw it".
Is there a reason for it to look like a gun? Maybe the format helps to concentrate? Maybe it just looks cool?
shrugs