Kurikara (5e Equipment)
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Wondrous item (longsword), legendary (requires attunement by a creature related to demons in an important way)
The Kurikara, or demon slaying sword is a legendary blade with the power to kill and contain demons and their power. The sword was primarily used to contain the demonic power of Rin Okumura, a son of Satan. When unsheathing the blade the used is fueled with the blue flames of Satan and their power exponentially increases. However there is a risk as the flames can potentially devour and disintegrate the user if the user get overly emotional or simply loses control. Apon drawing the sword, the user is wreathed in flames as per the Investiture of Flames spell.
You gain a +5 bonus to attack and damage rolls made with this weapon
Kurikara has 20 charges per day and recovers 1d10+5 charges at the end of a short or long rest. You can expend charges to cast the following spells.
Spells. While holding the staff, you can use an action to expend some of its charges to cast one of the following spells from it, using your spell save DC and spellcasting ability: produce flame (1 charge), burning hands (2 charges), continual flame (4 charges), fireball (6 charges), control flames (8 charges), flame strike (18 charges).
Rage. At the start of their turn with Kurikara unsheathed or whenever a spell is cast using the Kurikara, the user must make a DC 10 Wisdom save or enter a rage. Every success adds a +2 to the DC for a maximum of 24. A Good, Chaotic Good, or Lawful Good aligned character has advantage on this roll. While Raging under this item's effect, you cannot cast spells using natural ability or items such as Kurikara or a Wand of Magic Missile. While Raging under this item's effect, you must attack the closest creature to you every turn and take 2d10 fire damage at the start of your turn. At the end of your turn make a Wisdom saving throw equal to the save you failed when you entered rage. On a successful save the rage ends and the user gains 1 level of exhaustion for each turn raging (Max 5). On a failed save the user continues raging and the DC decreases by 2. If the user falls unconscious while raging the rage ends and the user gains 1 level of exhaustion.