I can't immediately find one, though I'd have thought someone would have done one. A few leaders are fairly obvious though (Montezuma, Shaka, Tokuwaga, Alexander and Isabella, if you don't share her religion, all tend to backstab.
I think you've misunderstood the term "backstab". All the leaders you mentioned are obviously hostile unless you go to great lengths (a shared religion, giving in to their demands for tribute) to appease them. But their attitude rating (usually "Annoyed" if not "Furious") and their interactions with you make their intentions clear. You should therefore be able to prepare to deal with them accordingly.
The back-stabbers are the ones who get to "Pleased" or even "Friendly" status and yet will still turn on you unexpectedly. Apparently Catherine is the most notorious for this. From what I understand Joao of Portugal falls into the same category. I've also had Kublai and Qin declare on me when at "Pleased" status. So I'd categorize them as back-stabbers, that is, quite capable of putting a knife in your back when you don't expect it, indeed, when you have worked very hard to ensure it won't happen.
ifinnem said:
Can anyone convince me that mounted units are useful pre-knght/elephant and even then a pikeman makes short work of them
Mounted units definitely have their uses.
Historically, they had two main advantages. First, their speed, allowing them to race around and attack an enemy on their flanks, where they're usually weakest. Second, their power--the horse itself is a weapon, thanks to its momentum, the combination of its weight and its speed. Mounted units were often capable of punching through infantry ranks (or attacking them on their flanks) and making a defensive line buckle. Even just their appearance could do this. It takes a very brave man to stand his ground when a beast several times his weight is charging towards him (let alone a horde of them) and its hoofs are making the very ground beneath his feet shake.
The game's use of units like Spearmen, Pikemen, and Riflemen to counter mounted units is not wholly inaccurate; traditionally, the way for infantry to defend against cavalry was to form up and present the horses with a seemingly-impenetrable line of sharp spear-points (in the case of Rifles, bayonets). No amount of training could overcome a horse's instinct for self-preservation when faced with such an obstacle.
Okay. History geek lecture over.
Chariots, as MrCynical mentioned, have been the counters to Axemen since Warlords came out. They also make excellent anti-barb units early in the game. Warriors and Axes both crumble before them, and the stand a good chance of defeating Archers on flat, open terrain.
Horse Archers are probably the most limited-use mounted units and this, I think, tends to lead a lot of players dismissing the entire category of units. They are quite vulnerable to Spearmen and are not an obvious counter to any unit. Nevertheless, those 2 moves come in quite handy sometimes when you want to deal with an enemy unit that's intruding on your territory and making a bee-line to a valuable resource. They can also foray out of a stack to attack a unit and then retreat back within it for protection. I especially like sending HAs against enemy Catapults.
War Elephants only have 1 move but their main advantage is their strength: 8. Of all their contemporary units, only Praetorians match that. War Elephants make excellent stack protectors so your precious City Raider Swordsmen don't end up defending against attacks. You can give them Combat I/Shock to give them better odds versus Spearmen, though I wouldn't go Spear-hunting with them. WEs also eat Archers for breakfast, so they are one of the best mounted units for use in city attacks despite the fact they can't get CR promotions, let alone Cover.
Knights are extremely valuable. They have tremendous strength for their era combined with rapid movement. They are also the only real counter to Crossbowmen, which the AI will spam annoyingly to hinder your Macemen and Pikes. Knights can also mow down Longbowmen (which is not historically realistic, but Civ often isn't).
I'm just getting used to
Cuirassiers but I'm finding I quite like them. Their strength means they actually have a pretty good chance of winning a fight against a Pikeman. If you're facing them they can be a problem because they don't have an obvious counter until Riflemen. I find I have to use Pikes or Knights with Combat I/II and Formation against them to have any success, and I usually have to weaken them first with a catapult or two.
The whole point of
Cavalry is to get to them before anyone else does, or especially before anyone gets Rifles. In BtS that has become much harder, but Cavalry are still very strong units for their era and can fulfill a lot of the functions of their earlier brethren. They can protect a stack, they can deal with pillagers, they can be moved to trouble areas quickly, and they mow down any and all units from earlier eras. While Rifles are officially their counter, it's a much more even match than any of the earlier era match-ups like Pikemen versus Knights. If you've ever sent a Combat I Rifleman out against a Combat I Cavalry, you know that success is not at all guaranteed.
The main point is to use each unit in Civ appropriately. In many ways the promotions are a clue. Mounted units can't get City Raider promotions. So why do so many players insist on attacking cities with them? That's clearly not what their best at. Yes, melee units are much slower-moving, but they're more effective at city-taking.