Legendary Coda

Audiotech Engineering: 18th level You've gained mastery over your modified instrument. As an action, you can end your enhanced song in a triumphant blast of power with an effect determined by the song you are playing. Once you've used this feature, you must complete a long rest before you can use it again.

Battle Crescendo

Choose up to 10 creatures of your choice that you can see and that can hear your song. Each must make a Constitution saving throw. On a failed save, a target takes 14d6 sonic damage and is stunned for 1d4+1 turns. On a success, it takes half damage and isn't stunned. If a creature is killed by this power, its head explodes.

Support Crescendo

Choose up to 10 creatures of your choice that you can see and that can hear your song. Once in the next minute, each creature can, as a free action in response to taking damage, choose to halve that damage. Additionally, if the damage would reduce them to 0 hit points, they are instead reduced to 1.

Disruption Crescendo

Choose up to 10 creatures of your choice that you can see and that can hear your song. Each creature must succeed on a Constitution saving throw or be paralyzed for 1d4+1 turns. If a creature affected by this feature is damaged in any way, the effect ends for that creature.