As two actions, you produce a loud trumpeting. Each creature in a cone must make a Fortitude saving throw.
On a failure, it is incapacitated until the end of its next turn.
Augment
You can augment this spell with the following options, expending mana for each option.
You can expend 1 additional mana so a creature is stunned instead of incapacitated.
You can expend 2 additional mana so the duration changes to 1 minute/mana, concentration and a creature is incapacitated for the duration. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.