Arcane Blast

An experimental beam of condensed energy streaks toward a creature within range. Make a ranged spell attack against the target. On a hit, the target takes 1d12 force damage.

The spell creates more than one beam when you reach higher levels: two beams at 5th level, three beams at 11th level, and four beams at 17th level. You can direct the beams at the same target or at different ones. Make a separate attack roll for each beam. 
If a beam does not hit a creature, the back blast of the spell then knocks you prone and the spell ends- losing access to whatever beams you may have had left to use.