Tier 6 (Hero Level 16)
Death Coil deals more damage and heals more the lower Arthas's current health is, to a maximum of 100% bonus damage and healing.
Patch changes[]
(Patch March 14, 2017) Note: Added Functionality: Now also affects the healing of Death Coil.
(Patch May 17, 2016) Note: Damage bonus reduced from 20% to 10% for each 10% of Health missing.