On the experimental server, I have a small build using vanilla redstone and pistons. So far, 2 blocks have disappeared as a result of pistons, likely as they are moved, although I cannot confirm this as my attempts to reproduce the issue have failed. In the space where the block was located before disappearing, or possibly the one the piston attempted to push it into, blocks cannot be placed and pistons cannot extend. Fluids also cannot be placed or flow into the block space, however items, players and other entities may freely pass through. @johnfg12 and @charmander196 also attempted to place blocks in the location, and checked the position using mod tools, without success.
Currently, the blocks with this issue are located at -145, 67, -52 and -151, 69, -58. Edit: I just attempted to drop sand into the hole, but it has remained in falling block state.
This also happens when you try to place sand on a pixelmon... were you trying to suffocate one?[DOUBLEPOST=1472987579][/DOUBLEPOST] Try pistons outside of a claim, Just to check if this is Grief prevention causing it. Also, you were not trying to put a pokeloot or any pixelmon blocks... right?
I was hoping that it would either replace the missing block or "pop off" like falling blocks do with torches. I had previously forced a crash with F3+C, which I apparently forgot to mention, and no entities were near to the affected area. I haven't been able to reproduce the issue outside of a claim, although I am not entirely certain as to the exact steps to reproduce anyway. No pixelmon blocks were in the area. The pistons were acting as simple gates with vanilla fences and a basic toggle latch with a redstone block.
