Outside the temple, it's time to head back to your ship. Do so, and speak with
Linebeck as usual. Tell him to set sail.
We may have gotten the Northeastern Sea Chart, but we don't need to go there
just yet. There's still one more island to explore at the Southeastern Sea. Set
a course for the Southeastern Sea, then once you get there, set a course for
the island at the northeastern corner which is surrounded by ice. As you sail
there, you'll have to shoot flying enemies that appear from the sky. Once you
get there, Linebeck suggests drawing a course around the icy island so that we
can blast the ice off of it. Set a course around the island a few times, and as
you sail around it, tap the ice and shoot each piece twice to sink it. Kill the
enemies that distract you while you do it. Once all of the ice is gone, you'll
be ready to set your course for the Isle of Frost.