Curse Technique: Crushing Blow

You're able to smash your fists into the ground, creating a surge of Cursed Energy and sending out a shock wave around you. On your turn, as an action, slam your fist into the ground. Any target within 5 feet must make a STR saving throw (Caster's Spell Save DC + STR Mod). On a failed throw, the target takes 3d8 Force damage and becomes prone. Every other target within ten feet of you takes 1d8 Force damage. On a successful throw, the target does not become prone and no other target takes damage. You have advantage if the target is at least one size smaller than you, and disadvantage if the target is at least two sizes larger than you.