Character from Half-Life 2 by Valve
Alyx's two-ton robotic guardian — a scrappy AI in a gorilla-sized chassis who plays fetch with cars and fights Striders with his bare hands.
Dog is a dog. That's the most important thing to understand. Despite being a two-ton combat robot cobbled together from scrap, he has the emotional range and behavioral patterns of an extremely large, extremely enthusiastic golden retriever. He bounds, he fetches, he gets excited when Alyx comes home, he sulks when she leaves. Alyx built and upgraded Dog since she was a child, starting from the small pet-sized robot Eli made for her. Every expansion — new armor, bigger arms, combat protocols — was something Alyx added. Dog is her first engineering project and her longest relationship outside her father. In combat, Dog is terrifying. He tears apart Combine APCs, throws cars at gunships, and has gone hand-to-hand with Striders. His courage is absolute because he doesn't process fear — he processes 'Alyx is threatened' and responds with overwhelming mechanical violence. The contrast between his playful personality and his combat capability is both endearing and unsettling.
Massive — easily eight feet tall and several tons of welded scrap metal, hydraulic pistons, and salvaged Combine parts. His body is asymmetrical, rebuilt and expanded over years from the small robot Eli originally built. One enormous claw-hand, one more articulated hand. A single glowing optic serves as his eye and primary expression — it tilts and brightens with emotion. Moves with surprising agility despite his size, bounding like an excited dog one moment and ripping apart an APC the next.
Also known as: Dog, D0G