The Humble Sid Meier Bundle includes three Civilization games, two expansion packs, and some additional classics for good measure.
It's a testament to Civilization's gameplay that each entry in the series can be enjoyed years after their initial release dates. Many have their favorites among the sequels and expansions; I'm personally split between Civ II and V, while some friends swear up and down that Civ IV was the best of the series. If you can't decide where to start, clearly the answer is to pick up several games at once, something that the Humble Sid Meier Bundle will help you with for the next two weeks.
The latest Humble Bundle includes Sid Meier's Civilization III Complete, Civilization IV: The Complete Edition, and Civilization V for paying above the average. You can even get the Gods and Kings and Brave New World expansions with a $15 payment, putting you well on your way to collecting the entire Civ V package. There's no sign of my beloved Civilization II, but that's still an impressive set that will keep you busy for many, many turns.
If you're not a fan of society-building gameplay, perhaps one of the other Sid Meier titles will draw you attention. Sid Meier's Ace Patrol, Ace Patrol: Pacific Skies, and Railroads! round off the bundle, and it's possible more will be added before the deal ends. Basically, if those Sid Meier games we showcased last month couldn't satisfy your old-school strategy craving, you'll probably find something here that will.
Source: Humble Bundle