Can someone be kind enough to add BTS videos and any extra scene links to this thread. I know many were shared in the comments section but it moves too fast. Plus, I haven't watched any to avoid spoilers.

If possible please include the related episode number if not mentioned so others can avoid if they haven't caught up.

Adding a few:

Dream arc scenes and explanation of the relationship between TTJ and LSS:
https://www.youtube.com/watch?v=7zN_kpdHvtU

YOUKU channel with BTS scenes:
https://www.youtube.com/@youku-official/videos

YOUKU English:
https://www.youtube.com/@youkuenglish/videos

Ep 28 - 29 trailer:
https://www.youtube.com/watch?v=BvvlQEhGMMk