Corruption

Shadows collect around the target, freezing it with the power of darkness and sapping away the essence of its life. The target must succeed a Constitution saving throw or take 1d4 shadow damage at the beginning of each of its turns and suffer a -1 penalty on saving throws as its life force is slowly stripped away.

At Higher Levels. When you cast this spell at 3rd level or higher, the damage over time effect increases by 1d4, and the target gets an additional -1 penalty on saving throws for each two spell levels above 1st.