Last time I was in the Hall of Guardians the bear was sunk into the floor. Could only see his back and ears.
#Hall of Guardians - Bear
kindred gorge
normal vine
I have also seen this happen to both Memory, Otu and Eres!
Memory and Eres went so far in the floor they couldn't even been seen anymore, and Otu basically just had his back and head poking above the ground.
Reloading the area fixed it, and I have no steps to recreate it. I can say at least that I'd used home teleport to the Foxy Den and then run outside, rather that direct portal teleporting to Fox Island, if that has any effect for recreating it.
slow jungle
Happened to me too. This was after defeating Grimnir, and I thought the guardians were simply gone, until I reached the bear, and saw just that. I assume the others were in the floor too, and unlike the larger bear, not sticking out. Next time I went to the Hall it was all good again.
spare glen
This happens to me too whenever I go back to the Hall of Guardians. Not just the Bear, but both wolves are sinked into the floor and I see their ears.