Lurid Pact is a Unique Ring in Diablo IV Season 15. It comes from The Butcher (Lair Boss loot table) - one guide S13 guide.
Unique power
Rampage deals [200 - 240]%[x] increased damage. Each enemy or demon killed by Rampage increases the size of the brute and its smashes by 5%, up to 50%.
Affixes
Willpower
Skill Ranks to Rampage
Where it drops
The Butcher (Lair Boss loot table) - one guide S13 guide