I have created a mud wall around my "estate" about 7-8 blocks high, just to keep monsters from getting too close to my house, especially creepers.
Sometimes when I wake up there can be one block just missing from my wall even though I never had anything trying to attack me the night before.
Is this an enemy damaging my wall or some sort of glitch?
This is Minecraft for the PS4 by the way
Best Answer
As mentioned in the comments, it sounds like an Enderman has come to visit. These creatures spawn in darkness and (amongst other things) will pick up certain blocks and move them around, as described on the Minecraft Wiki:
In terms of defending your home from Endermen, the answers to this question have some tips you may want to try. Alternatively, you can try building your home (and surrounding wall) out of materials that an Enderman can't move, such as stone or brick (the Wiki article has a full list of blocks that they can move.)