Brain Rot

You choose a target you can see. You cast a horrid curse targeting their mind and brains, forcing them to make a INT save using the casters DC dealing 3d8 Necrotic Damage, and a momentary 1d6 penalty to their Intelligence on a failed save, or half of the necrotic damage on a successful one.
The damage increases with the used spell slot level, adding another 1d8 Necrotic, and 1d6 penalty to Intelligence.