Steal the keys from the thugs, then sneak through the sewers to assassinate Sivert.
Assassin’s Creed: Unity guide – Sequence 3 Memory 2: Confession – Assassinate Sivert
If you want to complete the challenges here you’re going to have to be as sneaky as possible – not always an easy task. You can just muscle your way through this section, but I’ll favour a stealth approach in the walkthrough.
- Two kills from hiding spots
- Don’t trigger any alarms
Take a moment to orient yourself; Notre Dame is a large space, and it’s easy to get distracted by the beautiful recreation. You start near the bottom left corner of the Cathedral. Switch on eagle vision to locate the two thugs; it shouldn’t be hard.
Steal the Keys
You want to pickpocket these guys, but don’t just dash in madly. Climb up onto the nearby rooftops and follow along the left side of Notre Dame until they enter a building. You can then easily climb into the same building via a second-story window, sneak down the stairs and half-inch the keys. You won’t fail the mission if you get caught, but stealth is a good habit to get into.
Make a quick and clean get away and head on over to the opposite side of Notre Dame to watch for Duchesneau. He’ll patrol for a while and then meet with a priest. After that, you can kill him or leave him as you choose; it makes no difference. In either case, you’ll now be right near the entrance to Notre Dame itself; just proceed a little further along the Cathedral wall until you’re at the top right corner – diagonally opposite your starting position, in other words.
Near the top right corner of Notre Dame you should spot a sewer access point near a separate building. Take advantage of it by climbing down the ladder and taking the first left to reach a set of stairs and a button on the wall. Once past this point you should avoid triggering alarms if you want to complete the optional challenge, so make sure you evade or kill any suspicious guards before they can go into full alert.
Now that you’re inside Notre Dame you’re perfectly positioned to get one of the hidden spot kills for the optional challenge. There are two guards you need to sneak past, and one of them will grant you the opportunity you need; take it and ignore the other, ghosting past him.
In order to take out Sivert in true style, you’ll first want to clear out the two nearby guards. Flirt with danger by attracting their attention one at a time, then kill them from cover.
Sivert is over near the hay cart, so sneak your way into it, then activate eagle vision to spot him. When his bodyguard is close enough, kill him from the hay cart to complete the optional challenge.
Be patient while you wait for Sivert to wander into the confessional, then sneak quietly over to enter the other side of the booth. After a cut scene you’ll get a few button prompts, which will trigger a kill. This actually counts as a kill from a hiding spot, so if you missed one or the other above, you may get the challenge done now.
Escape the Area
You can make a very quick and clean get away by turning right as soon as you exit the confessional booth. There’s a lift right there; take it to reach a balcony. Use the keys on the window and have it away on your toesies.