It's a single target ability that does cleave damage. If you don't hit the target your aiming at, none of the people around the ability take any damage. You're not slamming the ground like Dawnbreaker. That doesn't require a target.

Similar scenario would be Silver Shards. "Fire an augmented Dawnguard Vampire Hunter's crossbow bolt to strike an enemy, dealing 820 Physical Damage. Fires additional bolts at other enemies near the initial target for 22% less damage."

The additional bolts only hit the other enemies if the first target is hit, still a single target ability, but it has cleave or splash damage.