Suppose you start a game on Terra and want to pick the AIs most likely to cross the sea and compete with you to colonize the New World. Which AIs should you pick? Most people would intuitively pick the AIs with a sea-oriented unique unit or unique building (Willem, Hannibal, Ragnar, and Joao). However, this analysis is incomplete. Becoming A Naval Power In order to become a strong naval power, the AI must research Optics to unlock Caravels. So which AI is going to get to Optics first? The AI uses a probabilistic method to decide what technologies to research. The game code defines seven Flavors for technologies (Culture, Gold, Growth, Military, Production, Religion, and Science). Technologies are assigned points in each of these Flavors. For example, Mining is valued at 8 Production, 5 Gold and 3 Science. The AIs are assigned Flavors as well. Eight leaders have a single-minded emphasis on just one Flavor, such as Isabella (Religion). The other 44 leaders have one Major Flavor and a second Minor Flavor (for example, Willem is a Gold/Science leader). When the AI has to choose what to research, the leader's values (10 for emphasis, 5 for major flavor, 2 for minor flavor) are multiplied by the tech's corresponding values (and if the tech has more than one matching value the two answers are added together). The tech with the highest total has a greater probability of being researched. As an example: Hatsheput's flavors are Culture/Religion (aka Culture 5, Religion 2). Let's make her choose between researching Aesthetics and Mathematics. Here are their flavors from the game-code: Aesthetics: 5 Culture, 2 Religion, 6 Science (a total of 13 points) Mathematics: 10 Science, 1 Military, 1 Production, and 2 Gold (total: 14 points) Mathematics has more total points, but Hatsheput only cares about Culture and Religion! Hatsheput values Aesthetics at 5x5=25 Culture + 2x2=4 Religion = 29 Hatsheput values Mathematics at 0 because it has nothing to do with Culture or Religion! While there is some randomness thrown in, the AI is likely to pick the highest-valued technology available. Therefore, Hatsheput usually techs Aesthetics in this scenario and ignores Mathematics. Bee-Lining To Optics So the question remains, which AIs are most likely to build Caravels and explore overseas? Well, here is a list of all the technologies needed to unlock Caravels (i.e. Optics and all of its prerequisites). As you can see, not all techs are created equal. The average for ancient and medieval technologies is 18 total points. Some techs have much more, and some much less. In addition there are technologies with hidden "Power" values. These values are there to make every AI leader prioritize these techs, regardless of their flavor preferences. That's because these techs are so crucial in unlocking important game features or military units. Here are the Power-rated technologies in the ancient and medieval eras, with Optics prerequisites in bold: With this in mind, let's go back to our list of Optics technologies, and we can see that it is divisible into three groups. First, Mining and Fishing are starting technologies. Second come the technologies with high, diverse points or high hidden Power. Lastly come the technologies with low overall points and low Power. The limiting factor is really Sailing, Compass and Optics. Most of the AIs will quickly tech Iron Working and Machinery because of their flavor or their hidden Power, so we don't need to worry about that. It's Sailing, Compass and Optics that are standing in the way of the AI discovering the New World. The value of Sailing, Compass and Optics is overwhelmingly concentrated in Science flavor. Therefore, only Science-flavored leaders have a chance to research Optics early on. While these 3 techs have some value in other flavors, they're vastly outweighed by the "favored" techs in those flavors. For example, a Military-minded AI like Ragnar is going to look at the Military value of Optics (3) and still prefer the Military values of Horseback Riding (8) and Feudalism (5). If we look at the 4 additional technologies a leader needs to go from Caravels to Galleons: It is again obvious that these are techs with far-below-average point totals, and a value overwhelmingly concentrated in Science flavor. AI: Which Science Guy? Not only are techs not created equal, but AI flavors are not created equal as well. The playing field is HEAVILY tilted towards Military, and Science is actually the least popular flavor among all the AIs: The AIs are a bunch of jocks! There is no overwhelmingly Science-focused leader and only 8 leaders place any value on Science at all. Here they are (and I've calculated the total value these AI leaders assign to Sailing + Compass + Optics in blue): We have successfully narrowed it down to 4 AIs who place a high value on the Optics tree and begin with one or more prerequisite technologies: Why Lincoln And Joao Rule The Seas The Carrack: Joao has the ability to carry Settlers and military units in his Caravel UU, the Carrack. Tech Trading: Peter is the most willing to trade techs with the human and the other AI leaders, followed by Joao and Lincoln. By contrast the notoriously isolationist Tokugawa is unlikely to trade at all. Unit Spamming And Warring: Building large militaries and conducting wars slows down the AI's technological progression. Tokugawa and Peter are rabid warmongers, while Joao is neutral and Lincoln is inclined to peace. For these reasons, Lincoln and Joao are the most likely AIs to discover a new continent.