Talk to Rabiah, west of town, on the south side of the lake, to assist her with her healing duties. This starts by retrieving three mwsicine pots that have sunk in the water. They're clumped by the pillar sticking out of the water, and Senu can hilight them easily for you.
The game will instruct you on how to dive for them- they're close enough together that you should be able to get all three in one breath. However, if you feel like lingering, there is other loot in the area as well.
Catch up with Rabiah at the House of Life, a ruined Temple south of town.
Talking with her will net an objective to exterminate the soldiers inside the Temple proper. Scan via Senu, then start with the guy at the gate- whistle him out and take him down.
Scale the left-hand wall and hop over to pillar for an easy aerial takedown of a guard in a tent. Move north to grab another guard, then continue to work your way west, felling enemies as you go.
When you reach the colonnade, use the pillars to get behind the roving soldiers. The last guard should be all by himself in the inner temple. Approach over the eastern wall to get the drop on him.
Return to Rabiah for mission completion.