Damian's Storm of Lightning Bugs

You summon a giant swarm of magic Lightning Bugs at a point within a 60 foot radius of you. The swarm is a sphere with a 20 foot radius from the point casted at.

Any creature within the sphere must make a Constitution saving throw; If they fail, they take 3d4 Poison damage and 3d10 Lightning damage and can not take a reaction while in the swarm and automatically take the damage again when they start their turn in the swarm. If they succeed, they only take half damage.

As a bonus action, you can move the swarm 20 feet in any direction.

At Higher Levels: When this spell is casted at 5th level or higher, this spell deals an additional 1d4 for poison damage and 1d10 for lightning damage for each slot level above 4th.