The 'Wait, That's Illegal' meme features a screenshot of the character Church (wearing Master Chief-style MJOLNIR armor) from the popular Halo-based machinima series Red vs. Blue. The specific line was first popularized as a reaction image on Reddit in early 2019, quickly becoming a staple for depicting situations that violate common sense, logic, or unwritten social rules. It is most commonly used when someone discovers a 'life hack' that feels like cheating or when an unexpected event occurs that seems to break the natural order of things. The meme’s longevity stems from its perfect blend of gaming nostalgia and its versatile application to almost any confusing or 'rule-breaking' scenario.