Bone Lance

You cause a spike of bone to extend from your own skeleton, skewering your foes. You take 1 piercing damage, and cause a line of bone to appear from yourself, forcing each creature in a 15 foot line that is 5 feet wide to make a Dexterity saving throw or take 3d6 piercing damage, at which point the bone retracts into your body.

Casting at higher levels: For each higher slot you use to cast the spell, you can increase the damage by 1d6 or increase the distance of the line by 5 feet, in any combination of those effects. (I.e, a third level spell slot used to cast Bone Lance can both increase the damage by 1d6 and increase the distance by 5 feet.)