Dimitri is an robot echidna who was originally Knuckles the Echidna's nemesis and a character in the Sonic the Hedgehog comics. However, in later issues his role as an antagonist comes to an end, as his previously villainous intentions for domination are replaced by more noble desires, such as reunifying the Dark Legion founded by his descendants with Echidna society.
Originally, Dimitri wore the dreadlocks of his species in braids and wore a scientist's lab coat. While in his Enerjak persona, Dimitri wore a ceremonial outfit created for ancient Echidna generals. It consisted of a golden faceplate, skirt, breastplate, and various bands of gold around the elbows, wrists, fingers, knees, and ankles. The rest of the outfit was blue, the rest of the helmet including a red gem in the forehead and openings that allowed the dreadlocks to stick out. When removed, his faceplate revealed the face of Dimitri, untouched by centuries of aging.
Upon losing his powers at the hands of the sorcerer Mammoth Mogul, Dimitri became an aged, wrinkled shadow of his former self; near death, his existence was perpetuated through the use of cybernetic implants, creating a metallic form composed of asymmetrical steel-gray components. His limbs include a three-fingered right hand, a left hand with standard fingers, a right foot with 2 toes and an elongated heel, and a left foot resembling a metal boot. Dimitri's right eye is a standard implant shared by several other characters, while his left eye is triangular; both eyes are red. In this form, he has only a small fraction of organic body visible, including his silver ring-adorned dreadlocks, his right leg above the knee, and his neck. Later, this body was immobilized and had to be mounted atop a flat, table-like surface with life support systems built in.
Eventually, his situation deteriorated to the point where Dimitri was reduced to his cyborg head, contained within a floating glass orb, though the explanation for this transformation is different for each situation.