Based on discussions with misharu - regional variants of Riolu and Lucario that live in desert regions. The designs are based loosely on Anubis and Wepwawet, as well as basic pharaonic aesthetics. Its evolution is still based on affection, though it evolves at night rather than day.

Riolu dex entry 1: Despite Riolu's mournful appearance, it is energetic and inquisitive and trains regularly in combat. It loves to sit on the prow of boats and look out over the water.
Riolu dex entry 2: Riolu's sensitivity to Aura and spirits allows it to find hidden items and secret passages. In old days, it was known as The Wayfinder.
Lucario dex entry 1: Though not a ghost itself, this forme of Lucario is closely attuned to spirits and can behave like a spectre. Its sharp gaze seems almost judgmental.
Lucario dex entry 2: The bony protrusions on its wrists, ankles, and tail take on bright colors from minerals in the surrounding desert. Its tail rattles softly as it moves about.

Background adapted from photographer Embalu on Morguefile.