Vectis

The plague of corrupted blood killed countless trolls and began one of the most terrifying periods in Zandalar's history. The constructs within Uldir studied the disease in search of a cure, but found that only isolation and extermination was effective. Unfortunately, as the facility's safeguards cracked apart, the plague was accidentally combined with a sample of G'huun's blood, creating a new entity that hungered for fresh victims.