The hero originally named “Pit Lord” in DotA is Underlord.
Pit Lord was the name used for the character in the original Warcraft III custom map Defense of the Ancients and its DotA Allstars era. When the hero was brought into Valve’s standalone Dota 2, he was presented under the name Underlord. His in-universe name is Vrogros, and he is associated with the Abyssal Horde.
Underlord is a strength hero known for controlling areas and punishing enemies who fight near his team. His abilities include Firestorm, which damages enemies in a targeted area, and Atrophy Aura, which weakens nearby opponents while helping Underlord gain attack damage from fallen enemy heroes.
The old and new names can cause confusion because both refer to the same hero across different versions of the game. The answer is not “Lion,” “Vengeful Spirit,” or “Abaddon”; those are separate heroes with unrelated identities and abilities. Underlord’s signature ultimate, Fiend’s Gate, also reflects his role as a powerful ruler of the Abyss.