In a game I'm involved in, we've been offered the opportunity to request certain magic items that we'd like to encounter, including custom items. Taking the offer, I'm interested in something along the lines of a Holy Avenger, but intended for a Barbarian.
Comparing it to the source, is this proposed item balanced for a Legendary item?
Weapon, legendary (requires attunement by a barbarian)
You gain a +3 bonus to attack and damage rolls made with this magic weapon. When you hit a fiend or a celestial with it, that creature takes an extra 2d10 necrotic damage.
While you hold the drawn weapon, it creates an aura in a 10-foot radius around you. All creatures hostile to you in the aura or who enter the aura for the first time on their turn must make a Charisma saving throw (DC = 8 + proficiency bonus + Con mod). On a failure, the creature has disadvantage on saving throws against spells and other magical effects while it remains in the aura. On a success, the aura does not affect the creature until the start of its next turn, when it must repeat the saving throw.
If you have 17 or more levels in the barbarian class, the radius of the aura increases to 30 feet.
Referenced materials when considering the design of this included:
- The Holy Avenger;
- Stinking Cloud and other spell effects which require ongoing saves regardless of previous successes or failures;
- Bestow Curse and Bane.
Compared to the effects of the Holy Avenger and its ability to sway a fight, is this proposed weapon balanced?