Vicious Twerk-ery

You use the magic stored inside every true bard's bottom, and start violently throwing it back. Due to ancient butt magic, this summons incredible thunder, knocks over, and may even kill the weak foe. This magic is normally shunned upon, as it is considered 'utterly unacceptable', 'unprofessional', and 'simply just gross' by most spellcasters. However, you should not let that stop you. Magic is magic, a dead opponent is a dead opponent, and your body (or rather butt-y) is, in fact, your choice.

Cantrip Upgrade. The damage increases by 1d8 when you reach levels 5 (2d8), 11 (3d8), and 17 (4d8).