This is Branden, an academy student turned Duke's guard turned kingdom's citizen.
First I have to say that this was mainly my fault and I wonder if anyone else is having the same issue. When I first won him, Branden appeared as a walker right away but curiously he also showed up in my storage just like a deco that you could place on your game board. So I took him out, placed him and realized he was invisible. When I clicked on him, there wasn't any timer but I could move him around and could even sell him for 0 coins. I couldn't put him back in storage, however, but this seemed to be harmless and fun so I didn't sell him. I'd periodically check on him and see that he was still there and I could still sell him any time I wanted. Time passed, I've forgotten about Branden until one day I was rearranging stuff around my kingdom and realized there was a dead pixel. There's obviously nothing there but I can't place anything on that square. This must be Branden, and I just needed to move him. BUT, I realized now that I could no longer select him. When I clicked on that spot, there seemed to be nothing there, yet it's blocked when I put stuff there. So now I just have a dead spot in my kingdom, what used to be invisible Branden and now becomes invisible, unselectable, unmovable, unsellable, and yet taking up one space.
Picture: I tried to put the griffin there but the square is occupied (red). There seems to be nothing there but it's occupied by the invisible inaccessible Branden.
Like I said it's mostly my fault. Should've sold him when I could. I don't know if S8 would be kind enough to fix it for me, but I hope y'all won't do the same lol.