Urby's 1999 Mercenary Grunts - Reimagined addon - Half-Life - Mod DB
Steam Workshop::Half-Life Robot Grunt
Alpha lookalike Grunts [Half-Life] [Mods]
Restored Human Grunt addon - Half-Life - Mod DB
Here's a headcanon: All the HECU grunts apart from Adrian look like the original grunt model and Adrian is the only one with the high definition look. : r/HalfLife
Human Grunt (old) image - In Deep mod for Half-Life - Mod DB