Half Life made me disappointed in the evolution of its genre. The maturity of Half Life’s story might be what most games learned from, but the relentless variety should have been the real source of inspiration. Its science facility was such an elegant way to seamlessly join a diverse set of gameplay themes, since it contextualizes even the strangest combinations of environments smoothly. Industrial plants justify slow-paced exploration where the facility itself is your enemy, and they somehow blend into cramped offices which allow for tense atmosphere where aliens could be hiding around any corner, which then connect to wide-open zones used for fast-paced gun battling. These general categories will also get a unique twist in each iteration, creating even more variety in a system that was already keeping you on your toes. Even with so many different styles of play, the smart pacing between sections and the connectivity of the facility keeps the game feeling cohesive, and if I had absolutely no historical context, I would still be impressed enough to say it's one of the better shooter campaigns I’ve ever played. That is until the very end levels, at least. I won’t spoil exactly what happens if you’re one of the two people who don't know how the game ends, but suffice to say, they went overboard in creating something unique and ended up with a confusing mess. That's just one stain on an otherwise great experience though, so it’s the tiny parenthetical to avoid disappointment during an otherwise fantastic game.