Geothermal Valley - Tossing Gourds
Make 5 shots with gourds.
You won't be able to complete this challenge until returning from the Flooded Archives (the Trinity soldiers will have left the area), but it's not a tough one. Head for the upper village, where you had to sneak or fight your way through to the cathedral, and go to the southwestern corner. Here you'll find a patch of gourds which you can pick up and toss into buckets. You need to make five shots: three over the fence by the patch, one up the ridge to the north, and one over the fence around the house to the south.