Hi, I'm a veteran video gamer. I typically know how to find out information pretty well, but this particular game - and perhaps I'm senile, or losing my edge.. but.. There are unusual, but very important tidbits which seemed to be missing in general about this game. After searching around a bit.. I've discovered what I almost consider 'secrets'? such as the following: Rivers impart a 25% modifier to trade routes? Uncertain if this is shown in the game. I found out about it via a website. I haven't validated it. Is this listed somewhere? Marble imbues a 15% modifier to building wonders. (this can be see in the in-game information highlight over production but.. you wouldn't know to plan for it otherwise) its scantly mentioned through the posts here. Are there other relatively hidden modifiers to this game as well? This seems to be the devil in the details kinda thing. Is there a central respository of Very Useful, but Obscure modifiers somewhere I'm missing? Also, considering team play with a friend of mine. I've found almost no mention of any team play modifiers in any official documentation, or how it impacts the game.. sure, there is the shared tech, which became obvious after a few with team play. but what are the others? Yet another question, if say, you give a Immortal (persian unique) to say, the zulus, can the zulus then upgrade that unit to a impi with the implication that they have both specials? I'm uncertain as to whether the Immortal ability is a promotion or just inherent. - I know that can make a difference. Another - I was thinking of a scenario where, yuo might create a army of epic proportions with.. the huns + mongols where the huns gift their horse archers to the mongols with the discovery of chivalry, which seems neat. Many other combinations more potent combos, come to mind as well.