Nevermind! I beat it today. It is definitely the hardest of the skills though. Took a lot of tries to complete the later levels.

The only recommendation I can make is to aim for the head in a way that makes your projectile pop up and come right back down. If you get good, you can hit multiple times on the same enemy. It definitely helps to have low might, so your projectile won't have as much momentum when it strikes the head. If you have a lot of might, your projectiles just ricochet off the enemies and makes it harder to get multiple hits.