Dark Mechawful.5

A Dark Mechawful.5 (known as Dark Mechawful 1.5 in PAL regions) is an enemy found in Mario & Luigi: Bowser's Inside Story. When Bowser, Mario, or Luigi destroy a Dark Mechawful and leave the ejecting head alone for a while, the head becomes a Dark Mechawful.5, gaining a new metal body. The differences between the two are: When Dark Mechawful.5 attacks, the numbers on its chest sometimes malfunction, making it tricky for Bowser to counter.
 * Dark Mechawful.5 stops the timer on its chest, while the Dark Mechawful doesn't.
 * Dark Mechawful.5 has more iron plating, increasing defense.