Earth cannon

you summon a cannon made with the earth below your feet, rocks and roots are scattered throughout the cannons body and warm magic energy can be felt coming off of the cannon, touch the ground with your hand and speak the word "Arise" and a medium-sized cannon will be molded right in front of you or within in space 30 ft from your radius, the cannon does 2d6 force damage, for every spell slot used above 1st level summon an additional cannon, your cannons can be fired as a bonus action on your turn after there initial summon, the damage increases at level (5,11,17) increasing by 1d6 per level boost.