Here's a Git commit showing the changes that BtS has made to Civ4HandicapInfos.xml. (Will need to click "Show diff" and scroll down for the Deity changes.) It shows some elements added by BtS, e.g. regarding colony maintenance. Due to those new (required) tags, one couldn't just copy the Warlords file into a mod for BtS. Free health and happiness were apparently one lower in WL, but that applied to most of the difficulty levels - including Noble, and therefore also hurt the AI players [
edit - no, on the contrary, see next paragraph]. The AI players had bigger combat advantages against Barbarians, namely 40% instead of 25% against non-Animal Barbarians, and an additional (I think) 70% instead of 40% against Animal Barbarians. On all difficulty levels, not just Deity. A free starting worker already on Monarch, two on Immortal and Deity. No third settler as far as I can tell. Only 60% food needed for AI city growth on Deity (BtS: 80%), also a bit less food needed on the lower levels. AI unit supply, upgrade costs(!) and inflation not flat on all difficulty levels (BtS: 50% upgrade and supply cost, 80% inflation), but decreasing with each level, reaching only 5% upgrade cost, 10% supply cost and 20% inflation on Deity. Only 20% AI war weariness (BtS 50%) on Deity, also less AI ww on the lower levels. That's all only based on interpreting those numbers in XML; I didn't play any games on higher difficulty levels before BtS came out.
Edit: I've launched a WL game to at least check the starting units. As expected, 2 settlers and 2 workers for the AI. Happiness and health one stricter for the human player, but, for the AI, actually one point more lenient. I had misread that in XML. Free happiness goes from 6 on Settler to 5 on Warlord, 4 on Prince, 3 on Emperor. In BtS, the progression stops at 4 on Prince. Free health always two lower than free happiness. So the AI with its Noble player handicap gets 1 more health and happiness in WL, the player on Deity (or even just Emperor) 1 less. Screenshots attached.
Patches for BtS (Git diffs
3.13,
3.17) made some small additional tweaks to colony maintenance and Barbarian activity. And an apparent oversight was fixed concerning the AI anti-Barbarian modifiers on Monarch.
Civ4HandicapInfos.xml contains pretty much all the variables for AI advantages. There are a few related settings in GlobalDefines.xml, e.g. the 10 free starting production in the first AI city, but none of those seem to have been changed by BtS. No AI advantages should be hidden in the C++ code – apart from visibility cheats and asymmetries in the diplomacy system, e.g. no demands/ pleas between AI players. So it should be pretty straightforward to apply the WL handicap settings through a mod. Maybe just drop the WL and BtS version of Civ4HandicapInfos.xml into WinMerge. Whether this is a good idea ... Presumably, the AI advantages were not (only) dialed down to make the highest levels easier to beat, but, mainly, because the inclusion of the Better AI mod (not to be confused with its successor Better BtS AI) made the AI more competent. Broader game design considerations may have also played a role.
