Gradient Joe is a Caucasian male with a black-to-white radial gradient for a head (though this color can change based on his emotion, particularly red when angered) Not much is known about his personality, as he does not speak, but Bugbo has stated that Gradient Joe is very clever. Instead of talking, he communicates through gestures or by writing on pieces of paper with a red marker. Joe's emotions are often expressed by his gradient, as seen in "Under the Oak". (The black does NOT change color, only the white.)

Bugbo is a generic bug with a tall, round stature and a round head, both in which are a reddish-pink. He has dark magenta limbs, green eyes, and sports a pair of cartoony antennae. Bugbo's eyes are also downturned, similarly to most characters within the webseries, and sit at the top of his head Bugbo is casual, calm, and collected. He is quite direct with his goals and at times behaves passive-aggressively, interrupting others often to get a point across such as towards Quentin Mayor or Gerbo. He is also known to be incredibly intimidating when his plan is stopped by another character, this usually persuading them enough to let him get his way. When something does not go according to plan, he normally looks for another way around it, or in some cases, by using his suggested abilities whenever necessary. This can be negating Quentin Mayor's skin and organs in Under the Oak or by simply asking himself, What Would Gradient Joe Do? He is quick to get rid of any obstacles in his way, no matter what or who that may be, and seems to have little regard for anybody who does. Bugbo's texture is also uncomfortably smooth, Bugbo very commonly influences Gerbo, like in Under the Oak, where he says that he should be careful about keeping too many secrets. Bugbo has a strong dislike for inconsistency, as he disapproves of a tree that he sees upon greeting Gerbo and directs Joe to cut it down soon after (Bro is pretty much nonchalant in any situation lol)

Gerbo is a lime-green, stylized spider with dark blue eyes. His eight legs are a darker shade than his body, and he has a lopsided smile, his lower lip going over the top of his mouth. He has cartoony and round antennae on his head, and much like other characters, has downturned eyes just below them. Gerbo is a dimwitted and childlike spider who is best friends with Bugbo. He often has fairly creative ideas, but they're quickly shut down by Bugbo in favor of his own plans, which Gerbo goes along with anyway. He is shown to have a caring heart for others and doesn't like it when things are unfair, such as the Hollow Clown being put out of business after all circuses were banned. He generally seems to be quite slow talking in comparison to other characters, and hangs around Bugbo most often, as he is usually the first person he runs into. Gerbo is very reliant on Bugbo, constantly “learning” from him, and technically following his lead. According to Bugbo, "He isn't very bright but is still fun to be around".

Hoppo is a light green grasshopper. Funnily enough, her design and color palette is more akin to actual real-life grasshoppers instead of the usual cartoony and colorful designs of the show, though with clear creative liberties in some parts. Her body, head and antennas are a light tone of green, while her limbs are a darker shade of green. She has wings, which she only ever uses for expression. Similarly to Bugbo, she is constantly smiling. Her eyes have no sclera, instead consisting of a big black pupils and brown irises. Like the rest of the cast, her eyes are the only part of her body that are shaded: the light source seems to be coming from above, causing the lower part of her eyes to become increasingly darker, giving a gradient effect. Although Hoppo is one of the main characters, very little is known about her as she is usually preoccupied with unknown or unusual matters offscreen, and only appears onscreen for less than half a minute at most. She always finishes her sentences with hysterical laughing. Hoppo is known for partaking in violent and/or morbid activities, such as committing warcrimes on a battlefield in Episode 3, A Familliar Foe, and taking Quentin Mayor's skeleton in Under The Oak.