Spit out a glob of corrosive bile that creates a 3.5m radius disease cloud on impact that lingers for 3s. Enemies that enter the cloud are afflicted with a debuff that deals 100% heartrune damage per second and reduces incoming healing by 30% and outgoing healing by 15% for 8s. Cloud sticks to enemies on direct hits.
Heartrunes under GS700 can be upgraded at a Stonecutting station.