a) Alexander draws off of RTW and not BI (you do not even need BI installed), though you do need to make sure RTW is patched to 1.5 before installing Alexander. So BI features (swimming, shieldwall, schiltrom, loyalty, religion, etc.) are not inherent within it.
b) Victory conditions can state a "survivor" which requires that a specific unique character survive in order for that faction to remain in the game; however, We are not sure if that can be used for anyone other than the initial 'Alexander' character. Needs more testing.
c) Mercenaries can be designated as ''faction-specified'' in the campaign merc pool file. In ALX.exe, you can specify regional mercenaries to be recruitable only by certain factions.
d) ''Descr_Model_Battle.txt'' model's entries are increaseded from RTW/BI's 250 max to 500 !
e) AI can be instructed in the ''Descr_Start'' file not to attack certain factions (unless at war already). There is ''ai_do_not_attack_faction'' in ''descr_strat'', which prohibits the AI to attack certain factions, except when they're at war!
f) Immortality trait can ensure that named characters do not die of natural causes!
g) However, ALX.exe cannot use the features of BI such as hording, shield wall, schilstrom and swimming.
j) The next big thing is, of course, the unique general models. You can have battle and strat model and portraits that cannot be used by any other general in the game.
We can use specific campaign models, battle models and portraits for all the initial characters.
This is the example of entry in ''descr_strat'':
character Denethor, named character, leader, age 50, , x 149, y 80, portrait denethor, strat_model denethor, battle_model denethor
The biggest difference between ALX.exe and vanilla or BI.exe are the hard coded limit's on DMB. There are confirmation's that some mod's based on ALX.exe have more that 330. - BI and vanilla are limited to 250 entries.
Victory conditions can state a "survivor" which requires that a specific unique character survive in order for that faction to remain in the game; however, it is uncertain if this can be used for anyone other than the initial 'Alexander' character. Needs more testing.
This survivor condition only works for the human player however. That is you will not finish the game unless your Fleader is dead or Fleader of your enemy.