The 'There Can Be Only One' meme originates from the Adult Swim cult classic 'Aqua Teen Hunger Force' (2003), specifically in the season 2 finale titled 'The Last One.' In this scene, the narcissistic and loud-mouthed Master Shake (voiced by Dana Snyder) parodies the 1986 film Highlander, declaring his supremacy over his roommates Meatwad (Dave Willis) and Frylock (Carey Means). The sequence captures Shake's over-the-top ego as he tries to eliminate any perceived competition with dramatic flair. Culturally, this clip is the go-to reaction for situations involving intense sibling rivalry, encountering someone with the same 'unique' fashion sense, or when two people in a group chat have the same name. It perfectly encapsulates feelings of territorial aggression and comedic gatekeeping. Popular captions include: 'When you walk into the party and see another person with your exact same niche hobby' or 'Me seeing the other dog in the neighborhood with the same name as mine.'