When Star Trek: Deep Space Nine debuted in January 1993, the series introduced fans to new characters and alien species. Perhaps the most intriguing was the mysterious shapeshifter Odo, who could take on any form but had trouble with faces. When the powerful Changelings, the founders of the villainous Dominion, were revealed, they chose to look like Odo despite being able to replicate humanoid faces perfectly. The detail, conceived of for practical, real-world reasons, inadvertently revealed a lot about these characters.
Source：https://www.cbr.com/star-trek-deep-space-nine-dominion-founders-odo-appearance/
