- Sabotage four alarm bells
- Three cover kills
Assistance Opportunity - Defend the Gravediggers
Make your way down to the street level and run to the southwest, turning into the graveyard when you see an opening on your left. Immediately turn left again, going down the stairs and following the tunnel until you see a chance to defend the gravediggers. We found it was best to do this by dropping a Smoke Bomb, then putting the hurt on some Templar scum. When it's over, you'll notice that the option for underground assistance is available.
Infiltration Opportunity - Retrieve the Plans
Continue to head east through the catacombs until you reach some stairs, stopping before you get to the top and using your Eagle Vision to identify two nearby guards. We tried to silently kill one, but we attracted the attention of the second. It didn't seem to matter, however, as we easily defeated him in a one-on-one fight.
Two of the four alarm bells you need to disable are near the exit of the catacombs, and if you use your Eagle Vision, you should spot them on your mini-map, as well as a nearby Brute. The Brute can be taken out with a cover kill, then move from one bell to the other and disable them. Just be careful of another guard hanging out near the second bell. It's in this area where you'll also find the plans you must retrieve in order to complete this objective.
Wait in a Haystack
Theoretically you could jump into a haystack and get on with killing your target, but complete the challenge to sabotage four alarm bells. There are only two more to go, the second of which is near the haystack you'll be hiding out in.
The third alarm bell is to the west, maybe even a little bit northwest, but either way it has two guards who aren't far away. We took the first down with a silent assassination, at which point the second foe noticed the body and came to investigate. We got this guy with a cover kill out of convenience.
Next up, you want to head southwest, spotting your final alarm bell beyond a gate and laying among quite a bit of rubble. We didn't see any opposition near this one, but that doesn't mean you won't. Always be sure to use your Eagle Vision and eliminate the prying eyes of nearby guards. When you sabotage this alarm, you'll complete the challenge.
Now all that's left to do is wait. Hop into the haystack that sits in the compound's west corner. You'll know you're in the right spot if you see a door and a lift. Take note of the lift for your escape later on.
As soon as you gain control, you'll see three guards in your immediate area. One is leaning against the haystack you're hiding in, but avoid going for the kill until you exit the haystack and snap into cover. Take the kill for part one of three to complete your challenge for three cover kills.
Next up, move forward and take cover behind the tombstone the guard is standing by. Make sure his pal isn't watching, then score your second cover kill. From here, wait for the final guard to spot the body, or let him get a glimpse of you. Either way, when he investigates you can get your third cover kill and complete the challenge.
All that's left is to kill Lafreniere. With the three guards down, follow the dirt path to the east, passing to the right of an open gate, then a fountain and finally hiding in the small shack with the curtain. After that, wait a couple of minutes until your target passes by, then score the assassination to complete your objective.
Escape the Area
Remember that lift that was next to the haystack you were hiding in? Well, when you exit your hiding spot you'll find it near the wall, just to the southwest. Sprint there, taking the lift to the rooftop and making your escape. When you're beyond the shaded area on your mini-map the memory will end.