Ballad of the Silent Night

 When you first cast a Ballad, you begin playing a song which contains several verses.  You determine the order in which the song goes through the verses, and a verse may be sung repeatedly on subsequent turns.  However, each Ballad must begin on verse 1 and ends after you sing the final verse.  Each verse (aside from the triggering verse which requires Casting Time) requires an action to sing, and if you ever don't use your action to sing the verse, the spell ends imediately.  On the turn that you sing another verse, that effect will take effect, either instantaneously or for the duration of the turn.  These effects don't affect creatures that are deafened, incapacitated, petrified, or unconscious.  If you are under water, this spell's range is reduced to 20'.  Another target that is under water is only affected by this spell if they are within 20' of you.

Verse 1: "The night was still and silent, the enemy knew not what was coming,"

Effect 1: While this verse is being sung, only your allies within range that you designate can hear it.  All other creatures hear the sounds of the natural habitat around you as you magically mask you and your allies movement.  Roll 1d4.  Add this result to your and your allies' within range Dexterity(Stealth) checks made to move silently.  Any creature besides the allies you designated that makes a Wisdom(Perception) check to find you or your allies must subtract the result from their total.

Verse 2: "the heroes were masked, hidden within nature,"

Effect 2: While this verse is being sung, only your allies within range that you designate can hear it.  All other creatures see the natural habitat around you as you magically mask you and your allies in nature.  Roll 1d4.  Add this result to your and your allies' within range Dexterity(Stealth) checks made to hide.  Any creature besides the allies you designated that makes a Wisdom(Perception) check to find you or your allies must subtract the result from their total.

Verse 3: "the path left behind diverged, and confused those that followed,"

Effect 3: While this verse is being sung, only your allies within range that you designate can hear it.  The area you are within magically changes the trail you left behind as you moved.  Roll 1d4.  Any creature other than the allies you designated that makes a Wisdom(Survival) check to track you and your designated allies must subtract the result from their total.

Final Verse: "the sounds of death unheard, as the heroes made their initial strike"

Final Verse Effect: While this verse is being sung, only your allies within range that you designate can hear it.  All other creatures within range must make a Wisdom saving throw.  On a failed save, the creatures are deafened for 1d4 rounds.