A friend of mine called this a park bench mimic. I think that sounds awesome.
A collage of the work put into this
Scene with the mimic hidden. You can see mimic blood on this, and rusted weaponry indicating traces of battle.
Scene with mimic exposed when an adventurer takes the bait.
A variation on signs that show a mimic is nearby
More variation on signs that show a mimic is nearby
The grey box I used to make this painting
Earlier stages of the painting process