I like the addition of being able to drag and pull boxes and barrels to solve puzzles.There are a couple scripted encounters that showcase how dangerous and ruthless the aliens (and the military) can be.Barney's auto-aiming is a nice addition that makes him seem like a more accomplished marksman than Gordon Freeman.Watching the effects of the resonance cascade through the eyes of the other occupants of Black Mesa is really interesting and gives you a new perspective on the game's story line.I own this game on Steam and have beaten it at medium difficulty. I still enjoyed the game, but was certainly not as impressed at the lower-quality graphics and weaker physics engine as I would have been if I played it when it was released. If I recall, I bought a collection of all the original Half-Life games when they were on sale on Steam, but it was only after I beat Half-Life 2.