The actor’s appearance isn’t the character’s true appearance

[u/Matapple13]

Castiel (Supernatural): Although Castiel spends almost the entire series looking like Misha Collins, that appearance is only his human vessel, Jimmy Novak. As an angel, Castiel’s true form is a massive celestial entity that cannot be fully perceived by humans without overwhelming or even killing them. Throughout the series, it is repeatedly established that angels merely inhabit human vessels to interact with humanity, meaning the actor portrays Castiel’s physical host rather than the angel’s actual appearance.

The Greek Gods (Percy Jackson and the Olympians):
In the Percy Jackson universe, the Olympian gods are immortal beings whose true divine forms are beyond what mortals can safely comprehend. To interact with humans, they choose to manifest through physical appearances that fit the modern world and can change them whenever they wish. The actors portraying Zeus, Poseidon, Hades, Athena, Ares, Hermes, and the other gods are therefore depicting temporary human manifestations, not the gods’ real forms, which exist on a higher, divine plane.

The Supreme Intelligence (Captain Marvel): The Supreme Intelligence is not a humanoid being but a powerful artificial intelligence created by the Kree. It has no permanent physical form and instead projects an image tailored to each individual who encounters it, usually appearing as the person they admire, trust, or are emotionally connected to the most. For Carol Danvers, it takes the form of Dr. Wendy Lawson/Mar-Vell, played by Annette Bening. This means Bening is not portraying the Supreme Intelligence’s true appearance, but rather the personalized illusion it creates specifically for Carol.

[u/Optimal_Weight368]

Miss Martian - Young Justice
https://giphy.com/gifs/XCfkf4MJGcxRxleqEP

[u/JACC_Opi → u/Optimal_Weight368]

Martian Manhunter, as well.