Among all TBS games, Civ V reigns supreme. It has hundreds of hours of replayability, endless variation, and a great blend of detailed micromanagement with a low skill floor for players who like to be less granular. I can load up a random game with a random leader, and play for hours taking my empire from the ancient era to the information age. I never get bored, and with the excellent modding community there's an infinite supply of new and enjoyable add-ons to finely tune your experience.

And all that's just the singleplayer!

Civ V multiplayer is great fun. Grab three or four of your friends, and compete for world domination while privately text chatting to team up and betray your allies. Once you include other human players, the real political intrigue gets involved and elevates the game to an even higher level of fun.

The only downsides to the game are minor ones. Namely it can be boring waiting for multiplayer wars to drag on with consecutive turns, and the game suffers without the (in my opinion must-have) G&K and BNW expansions.

I cannot recommend the game enough. Truly it's a testament to how great the game is, that IMO it surpasses its own sequel in quality! I suggest you purchase the complete bundle to get the expansions as well as some of the great DLC civs.