He is a cold, highly intelligent "mad scientist" driven by a near-insane god complex. Completely devoid of morality, he treats human beings as disposable test subjects and is willing to cross any ethical boundary to transcend mortal limits and artificial life. By the age of 85, the original Zandik's appearance is less ostentatious. His hair most closely resembles the style of segments 35 and 45, having not yet lost its blue color. He wears a plain white lab coat, black gloves, long blue drapery over his shoulders with a gold tip and blue gem on either end, a blue dress shirt, and a black collar or tie with a light-blue gem inlaid in gold at the center. He continues to use a cane for support, walking with a black cane with a golden handle, and wears a monocle on his right eye.

65 has the longest hair and wears a bulky dark coat with fur trim over a black suit, a raven mask (resembling that of a plague doctor) with a gold beak and blue lenses, and a dark top hat. 65 is also shown walking with a light blue cane with a hooked, golden handle.

25 dresses more like a worker in a lab, with a white cross-chest lab coat, forearm-length black gloves, a pair of silver-framed glasses, and a high-collared blue shirt.

Dottore's most prominent design is that of segment 35 (introduced as his Omega Build), seen as his in-game model. He has medium-length wavy blue hair that is slicked back and wears a pointed, beak-shaped black mask that covers his eyes but otherwise leaves the rest of his face exposed. He wears a long white coat over a blue dress shirt and cravat, with a raven-like accessory draped around his shoulders. Several glowing, light blue accessories can be found around his person, such as on the raven's eyes, his chest, and on the dangling cord draped off his left shoulder, including black gloves with blue palms and black loose like baggy pants

45 shares a similar appearance to 35, but has a large overcoat in a style shared by the other Fatui Harbingers.

He wears attire similar to that of an Akademiya student and a golden 4-pointed star shaped earring on his right ear

He is a small child who wears simple Sumeru-style garb of a light-colored robe with a dark collar and chest and black hems to the sleeves.

He wears a black coat over his shoulders with a furred collar and a scaled purple-white interior. He also wears a black turtleneck shirt with 6 gems near the collar, 3 on each side, along with a "V" shaped gem below the others. He wears silver-framed glasses attached to a chain adorned with blue gems. His eyes are a soft purple