Slitherine

Adding this to hexes sometimes add strange artifacts, looks like drunken workers have built it.
Also, if you repeatedly click on it it goes through different shades, getting lighter. Graphic glitch or is there some hidden functionality at play?
Finally, the wall resides in the decoration department. I think it would be better placed in Other since it prevents any units from entering the hex.

I am surprised that you combined two decorations in one hex successfully . . . so far. I am referring to the wall and the obstructions. I recall a time when I did something like this and subsequently tried to edit the situation. That is what caused fatal corruption to the scenario that I was working on.

I simply added the wall to the hexes without reflecting on the trip wires already in place...
These combos may of course be what causes the graphic glitches.

It's a ticklish situation. To my mind, with the possible exception of sea rocks, wall is the only decoration that actually does something in terms of impeding or facilitating movement. You are right about suggesting that wall belongs in Other and should be treated as such, not a Decoration. That would sort out the risky conflict that wall presents in conjunction with other decorations. I am 100% positive that when I attempted to move or change another decoration with wall in the same hex (trees, I remember), doing so destroyed my scenario.

Of course, in saying this, I am advocating the destruction of any scenario in which I have used the wall, such as Castle Itter, because any such change as we are discussing here will cause that previous work to fail.