If you know your Elden Ring lore, you'll be aware of Miquella and the Haligtree. In the game itself, the Haligtree is a tough, optional area you'll have to endure if you want to face the ultimate test of your gamer skill waiting at the end in Malenia. In the lore, it's a beautifully tragic place, fit for the worldbuilding of Miyazaki and GRRM.
Miquella, one of the demigod children of Radagon and Marika, formed the Haligtree in the hopes it could cure his twin sister Malenia of her scarlet rot. That wasn't to be, but dataminer Lance McDonald shows just how the Haligtree came about in a newly unveiled cutscene. In it, we see Miquella planting the seed of what would become the Haligtree, showing an unused video file which also had a couple of lines of spoken dialogue attached. Trying to get the event which would have sparked the cutscene didn't work out, but viewers can take a look at it in the video below:
<social>https://www.youtube.com/watch?v=SSUR7sVi7DU</social>
Elden Ring has a massive abundance of content, but its cutscenes are relatively rare outside of boss introductions. This would have been a great way to introduce us to Kindly Miquella, although it may have been too heavy of a hint at his involvement in the future DLC.