i dont think assassins are ment to be used without quicksaving and reloading, at least not in the vanilla version. I've tried that and i have to agree, it does not work.
However, I rarely have to load more than once, generally just moving your assassin next to his target and then attacking (instead of attacking from all the way) does the trick for me. Also i have to add, how on earth are you going to get your cardinals promoted without getting a few slots vacant in the cardinal college ? what? you say those guys die of natural causes? they do? wow, i'll have to look into that
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