"Kill the guards at the roadblock before they discover Bartolomeo's soldiers" - I get desynchronized?
I'm at a point in the story where I'm with some 50 mercenaries disguised as French soldiers. My objective is the text in the title, and 3 targets are marked on my map as "targets". By that I mean they have a red bullseye icon on them. I'm given 20 seconds.
The problem is; the second I kill one of them, I'm desynchronized! It makes no sense! I'm told to go kill them, and I lose if I do. I'm not exactly given much time to ponder on the situation either. I'm on my sixth attempt now. Every time I fail I have to walk for like 2 minutes to get to the point I failed.
Any thoughts?
Edit. I've even tried to run ahead and poison all the targets way ahead of when I'm given the objective. They don't even have the courtesy of dying before the objective timer has run out and I'm desynchronized. THIS OBJECTIVE IS IMPOSSIBLE
And also, I've lost count of the number of times I've retried this objective now. It's over 20 times.
I also found this one a bit annoying.
If I remember correctly you cannot let any of the three guards - or any other guards - see you attacking, or any of the bodies, before you succeed. In otherwords, you must not raise any sort of alarm during this sequence and have to kill stealthily.
Run ahead as much as you can (you don't have to wait for the timer to start!) and start by taking out the guard on the roof - otherwise he will spot you attacking the others - then pick off the guard to the side. Finally, attack the guard who confronts the mercenaries.
So, if I remember correctly, the plan of attack is:
Climb up and remove the roof guard.
Move over to near the confronting guard.
Shoot the stray guard with the crossbow, then immediately assassinate the confronting guard.
I finally solved this in a slightly different way than suggested by DMA57361. It seemed that if anyone saw you attacking one of the targets, even the regular guards, you'd get desynchronized. They didn't give a damn about seeing the targets die though.
That made the crossbow the perfect weapon. It also made the objective rather easy. I ran ahead and around the back of the buildings and picked off the lone target with a crossbow bolt. Then I hid around a corner while the two remaining targets confronted the mercenaries. I killed each one in succession with the crossbow, making sure to hide behind the corner between each kill. As long as nobody saw me while the target died, everything went fine.
The keyword for this objective; the crossbow.