I enjoyed playing Half-Life immensely, though there were a few parts of the game I found to be quite annoying. Overall the game was really well done, and although the game seemed more action and less puzzle, there were a few good puzzles to get through, though they tended to be fairly simple, and just looking around and listening to the scientists will get you through the game rather quickly. It blended science and video games really well, you can ignore the science behind it all if you want, but for fans of science fiction there is a great plot to get caught up in as well.
I played the game off of Steam, I don't know if this makes a difference or not, but the game was incredibly buggy, much more than I would expect for a ten year old game found online, you would think there would be bug fixes over the years. I mean I never expect a game to be bug free, but for the amount of game play I put into it I expected a lot less glitches and bugs. When I was playing Diddy Kong Racing for example I found a number of glitches, but I played that game over and over, especially on the multi-player, for the amount of hours I would expect to find more bugs. However I spent a lot less time on Half-Life (haven't replayed it or done multi-player yet) and already I have found a few dozen bugs. The guns wouldn't always reload when I wanted them to, this seemed to happen more so when I had a full ammo load and wanted my gun to re-load, it didn't matter if the gun was almost empty or almost full. I would have to switch guns and then switch back to reload. I would constantly get stuck in walls if I was by them when the load screen would appear, and there seemed to be a lot of invisible walls in Xen, Xen seemed to be really ill-designed. The things that looked like giant head crabs were for the most part attached to the ground, though I found a few that seemed to just randomly be floating. As well in Xen I managed to fall off the map into a black void, and I was stuck underneath the map, if I looked up I could see the bottoms of the map. I was stuck there until I reloaded, no way to get back up or kill myself.
The most annoying bug by far was the fan. First off, who designed this facility? I mean really have the fan on switch underneath the fan seemed like a major design flaw. "Johnson, we've got a mission for you, there's almost no chance of coming back from this one. We need you to turn on The Fan." For nearly anyone turning it on it was sure to be a suicide mission, I hate to imagine the amount of men required to turn it off. Speaking of turning that accursed fan off, let's get to my glitch. I managed to turn the fan on and get up the ladder, I then jumped on top of the fan, and it simply spun me around and around. I tried jumping a few times a fell through the fan and died. Now sadly I saved right after turning the fan on, so I was stuck on top of a quickly spinning fan. I realized if I could fall through the blades I could land on the platform, so a few thousand deaths later I finally landed on that platform, with about 13 of my health left. Now that the fan was off, it would lift me up. I managed to get past the rest of the monsters, head crabs and such, to the next health power-up, but it was tricky. I spent about 2 days stuck on this one area, trying to fall through the fan blades perfectly, to land on the platform, without dying.
The game was excellent to play, and getting it off Steam for a dollar was all the more sweeter, they were running a deal for the tenth anniversary. I really am looking forward to playing the rest of the games in the series, and the plot has me completely enthralled. Going through the game was fun, and I managed to fit in 3 levels a day or so, not including time spent on the fan. As long as you paid attention it was hard to get stuck anywhere, there were always clues on how to proceed if you looked around. The action was also really well done, with all the different monsters attacking you with different strategies, and the military was a nice touch. Having the guards follow you around was nice as well, at one point I had 4 guards following me, though sadly I had to leave them behind before getting to the military attack. The AI was excellent, with both your allies and enemies taking cover, and shooting with some degree of intelligence. The power-ups were in good locations, making some parts nicely difficult, but never too hard.