Hi,
I noticed that in monoliths, while in the Shrouded Plateau area, thorn totems (rather, healing totems with the Spriggan Form passive Spiked Totem) do not spawn when casted, but still consume mana.
This does not seem to happen with regular totems in human form.
I have a recorded a short video showcasing it, including all skill points, passives and gear here : ThornTotemBug - YouTube
I also attached the game log.
Player.log (4.1 MB)