Dhingy's Dangerous Discharge

Stored electricity is released in a dazzling barrage of lightning, focused on a point you choose within range.. Each creature in a 15-foot-radius sphere centered on that point must make a Dexterity saving throw. A target takes 5d8 Lightning damage on a failed save, or half as much damage on a successful one.

If a creature fails their saving throw, they suffer Static Discharge for 1 Minute. During Static Discharge, if an affected creature attempts to use their movement, they take 1d6 lightning damage for every 15 feet they move, and cannot take the Dash action. This Damage is triggered by any natural movement, such as the creature running or walking, but doesn't include movement by magical means, such as the flight spell.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d8 for each slot level above 3rd.