Diablo II: Lord of Destruction is an expansion pack for the hack and slash action role-playing game Diablo II. Unlike the original Diablo's expansion pack, Diablo: Hellfire, it is a first-party expansion developed by Blizzard North. From Wikipedia
Blizzard's first major expansion for Diablo 4 introduces a new class, storyline, and features, enhancing both narrative depth and gameplay mechanics.