The ingredient Elytra Ichor is collected from Elytra corpses.
3 guaranteed samples can be found, in the following places (magenta crosses on map):
Elytra Ichor is obtained from nearly every type of Elytra, including Dementia, Felldew, and Mania varieties. The only exception is the Felldew variant of the Elytra Hatchling. In nearly every place where Elytras appear, they are possible at all levels.
Places where respawning Elytras are guaranteed to appear at all levels are (red circles):
- Dunroot Burrow has 28 Elytra.
- Knotbone Chamber has 5 guaranteed Elytra (2 more likely based on probabilities of creatures appearing and being Elytras).
- Milchar has 3 guaranteed Elytra (4 more likely).
Elytras are likely but not guaranteed to appear at all levels in several caves (orange circles):