What happened was, in short, attacked an enemy from a distance, as my character and the enemy ran up to each other, the terrain just suddenly unloaded.
- I could no longer see my character model
- The terrain was just gone
- I could not interact with enemies or villagers
I don't have video, which would have been better, but I can provide images.
The image of the map just shows where it happened vaguely, I attacked a wolf, just under all the dark patches.
I tried re-logging, didn't work, the glitch was the same.
So then I tried closing and reopening the entire game, but the same result.
I'm just guessing this all happened by chance, doesn't look like a re-doable glitch, nevertheless I don't know how to undo it.