After all, Half-Life is the one about military occupations and alien invasions, while Portal is the one with the petty killer robot who sings ... Half-Life 2 has the eerie, mysterious G-Man ...
the metropolis is called Hazard City (Water Hazard is one of HL2’s most famous levels), you have a dog companion while Half-Life 2 has a robot called Dog, and the name Chemical-Burn even has a ...