I have played the Classic versions of the original game and from what I have played, Serious Sam HD: The First Encounter enhances the visuals of the original game and made some gameplay changes with a new engine to boot. Nevertheless, this HD remaster makes the original game even better and more fun to play with added secrets and Steam online play! You also have leaderboards so if you want to reach the top, try customizing the difficulty and get the most points as you can get. Serious Sam is fun and doing it again with modern graphics is great!

Unfortunately though, the online community in this game is pretty much gone, so if you plan on getting any other achievement that isn't single-player and maybe a few of the co-op ones, don't count on it, everyone has moved onto Fusion, BFE, and heck, all of TFE is ported over to Serious Sam HD: The Second Encounter through the Fusion DLC, where if you bought this game and TSE HD, you get both games on TSE HD anyways. Because of TSE HD and Fusion, TFE HD is pretty much there in your library and unless you're going for achievements and the leaderboard, you are better off playing it on Fusion or even TSE HD if you own that too.

Even then, if you buy any of the Serious Sam HD games (And soon to be BFE), you get the Fusion versions of any of the Encounters, so if you want an even more enhanced version of the games and have an online community, Fusion is pretty much your best bet.

However, it's still Serious Sam fun and the game itself is still enjoyable even after years since it was first launched in 2001, so whether you're new or old to the series, try out the HD games regardless. They're a good time and offer a great challenge that will really test your skills.

I have played the Classic versions of the original game and from what I have played, Serious Sam HD: The First Encounter enhances the visuals of the original game and made some gameplay changes with a new engine to boot. Nevertheless, this HD remaster makes the original game even better and more fun to play with added secrets and Steam online play! You also have leaderboards so if you want to reach the top, try customizing the difficulty and get the most points as you can get. Serious Sam is fun and doing it again with modern graphics is great! Unfortunately though, the online community in this game is pretty much gone, so if you plan on getting any other achievement that isn't single-player and maybe a few of the co-op ones, don't count on it, everyone has moved onto Fusion, BFE, and heck, all of TFE is ported over to Serious Sam HD: The Second Encounter through the Fusion DLC, where if you bought this game and TSE HD, you get both games on TSE HD anyways. Because of TSE HD and Fusion, TFE HD is pretty much there in your library and unless you're going for achievements and the leaderboard, you are better off playing it on Fusion or even TSE HD if you own that too. Even then, if you buy any of the Serious Sam HD games (And soon to be BFE), you get the Fusion versions of any of the Encounters, so if you want an even more enhanced version of the games and have an online community, Fusion is pretty much your best bet. However, it's still Serious Sam fun and the game itself is still enjoyable even after years since it was first launched in 2001, so whether you're new or old to the series, try out the HD games regardless. They're a good time and offer a great challenge that will really test your skills.