Also, mineralized parts/exoskeleton evolved during the Ediacaran.
Edit: Since the above article is unavailable, here is an alternative.
https://www.sciencedirect.com/science/article/pii/S2589004222019484
Also, guts evolved (or were already present) during the Ediacaran.
In cast people cannot access the article, here is another one from Nature:
https://www.nature.com/articles/s41467-019-13882-z