6 ethereal tendrils from ethersparks (wisps around the spires). This is an auto-update.
8 shambler seedlings from obol shamblers (not dreadleafs). Click the shambler seedling that drops on the ground after each kill.
6 Eidolites along the cliffs where the Harrowing Horde is. These are glowing gems/rocks. They look like the soft metal nodes for this tier, except with blue gems.