Playing as Seleucid. About 100 turns after Raphia, the Ptolemaics hadn't train any more stack (they did attack me with an army once but it was not a full stack). When I invaded Egypt, their army mostly consisted of generals without armies and Alexandria still have a plague (maybe it's the reason?). I conquered all settlements along the Nile without much resistances, killing a couple of wandering generals along the way, incuding one or two Pharaohs, and left Alexandria intact.
Needless to say, the campaign is quite boring now (including the incident that the Parthians laid siege my towns in Media but retreated the next turn). Is it a bug?