Frozen Drifts is the 5th chapter in Sword of the Sea. This guide contains all collectible locations and everything you need for trophies/achievements.
Collectibles Overview:
Frozen Drifts Collectibles
This area is largely linear, involving progressing through the area on the back of the shark you freed in the prior area. Destroying the ice blocks by dashing into them awards Astra.
Water Point #1 – In the first area, activate the lanterns to open the door to progress.
Water Point #2 – In the open area, activate the lanterns on the left to spawn large groups of Astra.
Water Point #3 – On the right of the area, break the crystal with the sphere inside.
Water Point #4/5 – Go around the left of the raised area where there is a group of lanterns that spawn Astra, along with the other crystal with a sphere inside.
Water Point #6 – Lanterns appear at the base of the pillar after activating the two water spheres.
Water Point #7 – After dropping into the next area, there are lanterns on the left near some ice that spawn Astra. If you want to break the ice blocks in the arches in this area you need to dash near hills to get airborne, as the shark can’t jump directly.
Water Point #8 – On the top of the first large hill is the first crystal with a sphere inside.
Water Point #9 – Just past the arch on the left is a group of lanterns that spawn Astra.
Water Point #10 – On the left of the tower is the second crystal with a sphere inside.
Water Point #11 – Past where the crystal was on the left is a group of lanterns that spawn Astra.
Water Point #12 – Lanterns appear at the base of the pillar after activating the two water spheres.
Water Point #13 – In the next area on the first hill is a group of lanterns that spawn Astra.
Water Point #14 – Go to the right of the raised area where there is a snow path leading to a set of lanterns that spawn Astra.
Water Point #15 – Keep going around the central area to find another snow path leading to a set of lanterns that spawn Astra.
Water Point #16 – On the raised platform to the right of the area is a crystal with a sphere inside.
Water Point #17 – To the left of the area near an arch is a group of lanterns that spawn Astra.
Water Point #18– Follow the snow path beside the raised area to find a group of lanterns that spawn Astra.
Water Point #19 – On the left raised platform is the second crystal with a sphere inside.
Water Point #20 – Around the back of the hill with the pillar is a group of lanterns that spawn a side area.
Secret Shell #33 – On the side area that appears after activating the lantern at the base of the sword you can find the single secret shell for the level, awarding Frozen Drifts Shell Collector 
.
Water Point #21 – Lanterns appear at the base of the pillar after activating the two water spheres, awarding Cleanse the Frozen Drifts .
NEXT: Sacred River
Wee Freeman says
There are 21 water points, you have 16 labeled twice.
Gage says
Corrected, thank you