Which Serious Sam?

ALL OF THEM!!!... No, I don't know. ^_^

2 is better, i still see people now and then.

Classics are great if you can handle outdated graphics. If not, try Serious Sam 2, it's more cartoon-like but fun as well. Random Encounter... meh.

I don't know about classics, but few weeks ago i played the First ecounter HD and it was empty.
I guess your best bet is SS2.

Out of those you've listed, SS2 would be the best to get. I wouldn't worry about the classics and would just skip straight to the HD version if you like SS2.

i wouldn't buy the classi serious sam games, they are garbage.

First and Second Encounter (HD) are the better of the series.

First or Second Encounters - they are the best =)

Why buy when u can trade them ? They were in 2-3 bundles so they are easy to get. If u have some spare bundle games u have a good chance. And the money u can put in another game. Try my library for bundle games i dont have or use steamtrades with yr bundle games.

Just so you know, Random Encounter doesn't work on windows 8, because it's made in older version of Game Maker and devs haven't updated it in forever and probably never will.

Now or never, best deal you'll get. ^_^

2