Crescendo

You start a gradually increasing melody and with each turn you concentrate on this spell its magic increases. If you use your action to use the counter charm feature you may cast this spell as a bonus action. When you cast this spell and at the start of each of your turns you and each creature of your choice within 100 ft. of you gains temporary hit points equal to the level of the slot you used to cast this spell. At the start of the second turn you concentrate on this spell and the start of each turn after each creature of your choice that can hear your music takes 3d6 psychic damage. At the start of the third turn you concentrate on this spell each creature dealt damage by it must succeed a wisdom saving throw or become frightened of you until the start of their next turn. At the start of the forth turn you concentrate on this spell and each turn after you may cast any 2nd level or lower spell you know that doesn't require concentration and has a casting time of one action as a bonus action at 2nd level without using a spell slot.