The Diglett Underground meme stems from the long-standing mystery within the Pokémon community regarding what the Pokémon Diglett looks like below the dirt. Since its debut in Generation I, Diglett has only ever been seen from the neck up, leading fans to create hilarious, often cursed, illustrations of what lies beneath—ranging from incredibly muscular humanoids to sprawling subterranean monsters. The meme is primarily used as a metaphor for the tip of the iceberg, where a simple or calm exterior masks a complex, intense, or bizarre reality underneath. It remains a staple of Pokémon humor, constantly evolving with new fan interpretations of the Pokémon's hidden physique.