Swarm of Insects

Swarming insects of your choice fill a 20-foot-radius sphere centered on a point you choose within range. The sphere spreads around corners. The sphere remains for the duration, and its area is lightly obscured. The sphere's area is difficult terrain.

When the area appears, each creature in it must make a Constitution saving throw. A creature takes 3d8 piercing damage on a failed save, or half as much damage on a successful one. On a failed save, the creature also suffers an effect of your choosing, depending on the type of insect:

Hornets. The creature takes an additional 1d8 poison damage, and becomes poisoned. The creature can repeat the saving throw at the end of each of its turns, ending the effect on themselves on a success.

Termites. The creature becomes blinded as termites swarm across it, and any nonmagical weapons with wooden components (e.g. swords, staffs) the creature is holding suffer a permanent and cumulative -1 penalty to attack and damage rolls at the start of each of its turns. The creature can repeat the saving throw at the end of each of its turns, ending the effect on themselves on a success. Magical plants, plant creatures, and constructs made out of wood have disadvantage on the saving throw, and you have advantage on damage rolls against them with this spell.

Flies. The creature takes an additional 1d8 necrotic damage, and its hit point maximum is reduced by the amount of necrotic damage taken. This reduction lasts until the target finishes a long rest. The creature also has disadvantage on saving throws to maintain concentration. The creature can repeat the saving throw at the end of each of its turns, ending the effect on themselves on a success.

A creature must also make this saving throw when it enters the spell's area for the first time on a turn or ends its turn there. 

At Higher Levels. When you cast this spell using a spell slot of 6th level or higher, the damage increases by 1d8 for each slot level above 5th.