: The Black Mesa Research Facility is a character in itself. Moving from sterile labs to industrial sewer systems and eventually the alien world of Xen creates a sense of scale and progression that still feels cohesive today.

: This edition is the definitive way to play, often bundled with the excellent expansions Opposing Force and Blue Shift , which offer fascinating "side-quel" perspectives of the disaster. Modern Compatibility

: Unlike its contemporaries, Half-Life never pulls you out of the action for a cutscene. You see the "Resonance Cascade" and the ensuing chaos through Gordon's eyes, making the dread and urgency feel personal.