The phrase represents a specific type of disguise worn during the Halloween holiday. It combines a popular science fiction franchise character with a celebratory tradition. More specifically, it references attire designed to resemble the Decepticon leader, Megatron, from the Transformers universe, and intended for use as part of a Halloween celebration.
This sort of costume leverages the character’s established image of power and villainy, elements that resonate with some individuals seeking to embody a particular persona during Halloween. The concept benefits from the pre-existing popularity of the Transformers franchise, offering a recognizable and potentially elaborate option for individuals interested in dressing up for Halloween. The desire to emulate well-known characters during holidays is a long-standing cultural phenomenon.