What is the role of の in 「怒りのキーブレード」？Why is it translated as "the keyblade's rage" and not "the keyblade of rage"? This is in the context of a videogame. The complete quote is , which was translated into "The keyblade's rage releases those hearts". Why isn't it "The keyblade of rage releases those hearts"? What is the role of here?

This type of is found often in fictional works and adds a "symbolic title" to the modified word. Similar examples:

* (The Statue of Liberty)
* (Attack on Titan)
* (Fullmetal Alchemist)
* (Blue Exorcist)
* (Demon Slayer)



Official English translations are included in parentheses. As you can see, this construction is not always translated "literally" into English. If there was a weapon whose official name is , then it could be translated as "Rage Keyblade", "The Keyblade of Rage" or something like that. However that's not the case in your sentence. Since this seems to refer to someone's keyblade who happens to be in a fury, "the keyblade of rage" might sound too grandiose, and "the keyblade's rage" seems to be a possible translation to me.