Sparking Guitar (5e Equipment)
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When a non-bard tries to use the item, he/she rolls a d8:
If you're attuned (as bard) and you touch it, two floating disks (like those from floating disk spell) containing two sound-amplifiers spawn within 5 ft. from you. You can use your bonus action to move both disks (within a range of 10ft. of you) mentally. You can also rotate them to face your opponents.
The Sparking Guitar has 7 charges and regains 1d6 + 1 charges daily at dawn.
Sound Wave. Both amplifiers emit an huge soundwave (this ability has no effect on constructs or deafened creatures). All creatures withing a 100-feet cone (starting from the disks) must make a DC (8 + your Charisma modifier) Constitution saving throw to take half of the 6d10 thunder damage and not be deafened for 24 hours or until their hearing is restored with a lesser restoration or better spell.