en 1.9 to 1.10.2 /summon Game mods Throw a diamond pickaxe on a dropper to craft a block breaker.
Throw the block breaker on an iron block to place it (if you place it manually, it will just place a normal dispenser !). You will get the iron block back, don't be afraid for it :)
You can retrieve the block breaker if the dispenser is dropped (meaning you have to use the correct pickaxe and be in survival).

Each time you activate the block breaker, it will break the block beneath it.
To activate the block breaker, place ON TOP:
- A button (stone and wood) placed directly attached to the block breaker
- A lever (which will do a constant redstone signal) placed directly attached to the block breaker too
- A redstone block
- A redstone torch

So it won't work for pressure plates and redstone dust.