In season 6 episode 19, Lydia had a premonition that her allies turned to stone.
https://www.youtube.com/watch?v=dPodXPfTs8YIt really happened on episode 20. Since I know everyone here just loves clips. I saw one on youtube.
https://www.youtube.com/watch?v=-jfNCCTwqskFor the restoration of Malia, I didn't see youtube clips. Just in full length videos.
https://watch-series.co/series/teen-wolf-season-6-episode-2039:02