https://www.youtube.com/watch?v=Fjjf_RuwRO8
Assassin's Creed Unity
Memory: The Kingdom of Beggars
Style: Lethal / Stealth Reaper / Stealth Kills
There's a group of three guards that spawns in with the memory, but they never re-enter the area so I don't go out of my way to kill them. They're the ones that are walking ahead of me after I turn the first corner to kill the two sentries standing guard by the ruined house. There's also another group of three guards inside an attic that is only accessible by a ladder-hatch from the roof. I skip them too because they're not really part of the memory; they're guarding a Red/Lockpick Chest and the Memory just happens to be placed near them.
A Non-Lethal version of this video wherein I actually finish the mission is coming soon.
Safety and peace.