The power of games vs. other forms of media, to me, comes from interactivity. Whereas a book can tell you something, only a game can force you to understand something through your own actions. While a movie may be able to show you the motivations of someone, a game can motivate you to act like that someone, or to think like that someone, at least in a limited sense.
Opera Omnia is a rare example of a game that takes full advantage of the unique benefit of interactivity. The idea is that you are, basically, a historian that tries to work out what happened in the past to create the population you have using a wonderfully simple program that accurately tracks the migration routes and growth rates of the citizens.
However, (and if you haven’t played the game then stop reading now,) you come to find out that what you are doing isn’t that accurate at all. In fact, you’re really trying to create a scenario that can account for the future while making the past whatever you want it to be. There’s a reason that he put the present on the left and the past on the right; the modification of the past is your end goal. This is a difficult realization to come to, frankly, because it’s just so backwards from what anyone would normally do.
It took me about 15 of the game’s 20 stages to finally come to that realization, but when I did, it was pretty amazing. Not only do you have to “play” the system to win, but that’s the whole point. In the end, you basically justify the genocide of an entire race by exploiting the system that you are given.
So in that sense, Opera Omnia makes you think, not just act, like the character you are playing. Any game can force you to act like somebody. The Doom Guy would blast through zombie marines from hell with a shotgun, sure, but you do it because that’s the only way to proceed with the game. You have no motivation other than that.
Opera Omnia motivates you with a goal, sure, but to reach that goal, you have to come to certain conclusions on your own, such as the malleability of “facts” and history, and how easy it is to come out with a “scientific” conclusion based on your own opinion.
It’s not perfect. There are a couple of stages that maybe explain a bit TOO much, and the last stage is a disappointment as far as the puzzle itself, but I’d say it’s a pretty good use of thirty minutes to an hour.
And beyond all of that, it’s just fun as hell to play.
P.S. My computer exploded in a violent ball of fiery flames (or just started acting funny and I broke it, whatever) so, uh, updates may be slow to come. Yay.