Sword Barrage

You reach out your hands, mutter some words, and summon small portals covering the sky with blades firing at everything in its path. Each creature in a 20-foot cube must succeed on a Dexterity saving throw. A creature takes 3d8 force damage on a failed save, or half as much damage on a successful one. This spell ignores half cover.

The portals remain open for 1 minute, or until concentration is broken. As an Action the caster can close and reopen the portals moving the cube within 60-feet of the caster, and as a Bonus Action the portals can summon more blades making each creature do another Dexterity saving throw if concentration is maintained.

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the damage increases by 1d8 for each slot level above 2nd.