Landscape glitch in Iceclad.
 

If you go to 3568, -2805 in iceclad there is a out of place looking part of a iceberg sticking out of the big iceberg thats in that location. If you get to close to the weird looking part of it you get stuck inside. I had to /rewind to get back out. Also that note does the planking spawn underwater too or is it a ground only spawn?

I can confirm it drops underwater, thats where i found mine, Southwest of gnome isle in the waters surrounding the stepping stones