Headcanons for Soul's future music-based wavelength-tampering abilities:
If Soul Adagio (play it slowly and with ease) is about slowing down the enemy until they became lethargic, then we can have:
Soul Allegro: (play fast and bright) the opposite of Adagio. If Adagio sorta acts like a noise canceller, then Allegro is like an amplifier, it fires up whoever hears it and energizes them in combat for maximum performance.
Soul Fortissimo: (play very loudly) increase the target's damage output.
Soul Pianissimo: (play very quietly) decrease the target's damage output.
Soul Legato: (play smoothly without gaps between notes) smooth out connectivity between linked souls during group resonance. Most useful when there's outside disturbance or the people resonating are being difficult.
Soul Staccato: (play shortly and detachedly) snaps each individual when resonance connectivity became overwhelming. Allowing participants to breathe at a less brisk pace. Can be used to forcefully severe connectivity like cutting through cables. Works almost like Crona's resonance disturber though without hurting and throwing the targets' wavelengths in disarray. More instantaneous and painless.
Soul Tenuto: (play for its full time value) improves each participants' individual focus, precision, and damage output. However, lower connectivity between participants. They say when Soul use this mode it feels they were receiving headpats from him.
Ascending: increase attack precision
Descending: increase evasion
Soul Marcato: Just a more intense Soul Tenuto. You might as well be receiving back rubs from him.
Soul Rubato: Bewilder the enemy by creating a rhythmical illusion where the user's attacks move deceptively slow or impossibly fast.
Soul Fermata: Cease connection but concentrates accumulated power into a single point.
Soul Caesura: Abruptly cease resonance. Pretty painful and can leave subjects bewildered.
Soul Smorzando: If an enemy has wavelength tampering powers, then the user is protected from being hijacked since the enemy's usurping wavelengths are smothered into nothing. (The 'I won't let you touch my meister' declaration wavelength protection form)
Soul Discordante: Works exactly like Crona's resonance disturber power. Force-shuts everyone's wavelengths and leaves them unable to properly connect afterwards without burning each other.