Take Back the Lion

Take Back the Lion is a quest that immediately starts as soon as you enter Emprise du Lion. You can speak with Mistress Poulin to receive more information but it is not necessary. Make sure your potions are fully stocked before continuing.

Walkthrough
After the quest is triggered, a search area will appear on your map to the southwest of the first camp. The search area is across the river, and you'll have to fight through several small bands of enemies to get there. Once you arrive, you'll have to fight about a half-dozen red templars, and they'll put up a good fight given that they'll be at Level 19 (it is possible if you are at least lvl 10). You won't need any special tactics to kill them, but take out the ranged enemies first, as they do the most damage.

Once the area is clear, claim the camp. You will repeat this process a few more times. Your next target lies to the east, but to reach it, you need to go west through your new camp. The way had been blocked by a palisade wall, but with the camp claimed, it's clear. You'll enter a cave system that curves south and goes around east while climbing in altitude. You'll have a few fights on your way, but the path is basically linear.

When the caves end, you'll fight another group of a half-dozen templars, including a red templar behemoth, which you can see in the above screenshot. Keep in mind that it's weak to ice. Beyond that, you'll find another contingent of about nine red templars, but they're no stronger than what you've faced so far. Kill them all, then claim the camp to advance the quest.

Once more the quest updates. Exit out the camp to the east and you'll pass into a little cave. Turn south when you can, and you'll have to close a rift. Keep going south, and you'll pass through a small open archway. Continue south as the path bends slightly southwest, then turn back west when you can. You'll encounter a small group of red templars.

To the west you will see some stairs.

Head up the stairs, then follow the wooden catwalk as it curves back around. You'll engage a red templar behemoth by its lonesome, then you'll be able to claim the next camp. This quest will lead into Capturing Suledin Keep.