Cold Heart Grip

After harming a creature within range, you grip their heart with a cold embrace. When you damage a creature with a weapon attack, as a reaction you may add an additional 2d6 cold damage.

If the creature damaged by this spell reaches 0 hit points their heart explodes into shards of ice. When this happens all creatures within 10 feet must succeed a wisdom saving throw or become frightened. 

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, this spell gains 5 feet in radius for each slot level above 1st.