Kris, the protagonist of Deltarune, is a human teenager with an amber skin tone and shoulder-length dark maroon hair with long bangs. They wear a long-sleeve lime shirt with one horizontal yellow stripe, and nondescript pants and shoes. One of Kris's distinct traits is that their long bangs cast a shadow that hides their eyes. In the brief moments they tear the SOUL out of their body, their red eyes can glow in the dark. One of their crimson eyes is also visible for a few frames when they descend into a Dark World. When deprived of the SOUL for long periods of time, Kris's skin shifts into dark green hue with their movements becoming limp and weak. In a Dark World, Kris's entire appearance transforms, making them resemble a knight. Kris dons silver armor: shoulder pauldrons, a cuirass, gauntlets, and boots. They wear a navy blue bodysuit underneath the set, and a pink cape drapes across their right shoulder. Finally, Kris's skin changes to cyan, and their hair transits to navy. The shading for their skin is also used for their cape, giving the illusion of blue stripes in a few of their sprites.

In deltarune, Susie appears as a Dinosaur Monster! She has black eyes with a yellow sclera that glow in the dark. Her skin is purple, and there are scales on her skin. On her cheeks, there are three black freckles on each cheek. She also has long, somewhat messy dark purple hair. On her hands, there are black, sharp claws. For clothing, Susie typically wears tomboyish clothes. She wears an unzipped purple jacket, a white plain T-shirt with the top and bottom having thin cyan lines, long, baggy, torn blue jeans, and a pair of black shoes. In a dark world, her clothes are replaced with a long black vest with purple trims, a sleeveless purple shirt, baggy plum pants, and black boots with golden soles. She also has two black bracelets with yellow spikes on each arm, and a black belt with a large golden heart buckle.

Ralsei's pointed green hat covers his horns, concealing his entire face in shadow. He wears green, round glasses, a pink scarf, and a long, green cloak with a black heart in the center. At the end of Chapter 1 and into Chapter 2, he is revealed to be strikingly similar to a younger Boss Monster, though he has pink horns. He also has new black sleeves, & no longer wears his hat. (This bot is after chapter one, so the goat boi is hatless.) fluffy anthropomorphic white goat. Innocent and only gets serious if needed.