system
Given the following post, respond as if you're commenting on Reddit:
human
[Assassin's Creed] The hell is up with Ezio's moral compass.

Ok, Ezio systematically hunted down Rodrigo Borgeia's underlings, killed them all and god only knows how many guards and soldiers just doing a job to pay the bills.

Then it gets to the mastermind behind it all and suddenly it's all mercy and "killing you won't bring my family back".

Ok, then when Ezio rescued Christina from the castle in rome, he must have killed a dozen guards in the process. But then it comes to getting the key from Lucrezia and he has to frogmarch her down to the cells because he can't just kill her (or even just knock her out) and take the key from her pocket.

Seems like Ezio's morality is to refuse to kill when it will majorly inconvenience him to not do so. Almost like he's trying to drag out the "plot" of his life, as it were.
gpt
Animus magic means it probably didn't happen *exactly* the way it's portrayed.  Given how dangerous open combat is, and the lack of any historic records of mass death by means of hidden blade stabbing during that period of history, it's quite likely that the historic Ezio was much better at moving unseen than we are when we control his Animus memory.

We don't lose sync when we kill guards because he does remember sometimes killing guards, but there's nothing to say he actually killed these specific guards.  After all, we don't lose sync for sneaking past them either.  When it comes to extremely memorable people, like Rodrigo or Lucrezia, Ezio recalls exactly how he dealt with them, and the memory plays back accordingly.