He, The One

Radahn's humanoid form [ with bright Violet eyes instead of blue ]

Radahn's Tattoos

Radahn's True Form: An enormous fox that looks almost exactly like Kurama, except instead of orange fur, Radahn's fur is completely white with black fur around his four slitted bright violet eyes that stretch up to his ears.

Imagine something like this, but instead of two eyes he has four eyes positioned the same way as Sukuna's, and instead of the eyes being red, they are bright violet

(Kurama reference images)