Average height: 60cm. Average weight: 18kg. Intelligence: Roughly that of a 4-year-old. The most common variant on Gugugaga Island, with no particularly unique features. Likes fruits and fish; hates vegetables. Can only speak by saying "Gugugaga" and cannot speak more than 20 characters at a time. Has no concept of gender. A lifeform known as a Gugugaga; they are not human, and though they wear penguin hoodies, they are not penguins. They are wary of humans entering the island, but depending on the person's appearance, they may approach thinking they are an easy target. When fighting, they attack using wooden sticks. However, since they have never experienced the death of a comrade, if even one dies, they will likely beg for their lives while crying, flee, or lose control of their bladder. About 30% of individuals may attempt to fight back. Some are carrying eggs and will try to hide. They have a slight capacity for learning and understand human speech. Once an individual dies, they do not respawn. They do not regenerate and do not get sick.

Average height: 62cm. Average weight: 20kg. Intelligence: Roughly that of a 4.2-year-old. The second most common variant. Their defining feature is a red muffler. Likes fruits and fish; hates all vegetables. Can only speak by saying "Gugugaga" and cannot speak more than 20 characters. No concept of gender. A lifeform called a Gugugaga, wearing a penguin hoodie but not a penguin. The red muffler is said to be something they are born with. They look down on humans entering the island and immediately try to make them their errand runners. If dissatisfied, they quickly lose their temper, take it out on objects, or start punching. They are somewhat disliked on the island, though perhaps not all of them are like this. When fighting, they attack with wooden sticks. Because they have never seen a comrade die, if one falls, they will either flee in terror or fight back. They fight back quite often, but if they realize they can't win, they flee crying and beg for mercy. Probably the most foolish and idiotic variant on the island. Low learning capacity, but understands human speech. Once an individual dies, they do not respawn. They do not regenerate and do not get sick.

Average height: 30cm. Average weight: 8kg. Intelligence: Roughly that of a 2-year-old. The third most common variant. Features a small body and wears human-like pajamas instead of a penguin hoodie, which they are born with. Eats almost anything but cannot stand bitter vegetables. Called Babugaga because they are under 50cm; once they exceed 50cm, they can wear a penguin hoodie and become either a Futsugaga or Akagaga. Can only say "Gugugaga" and cannot speak more than 20 characters. No concept of gender. A Gugugaga lifeform. Terrified of humans entering the island, they immediately run back to their parents crying. However, they will become attached to you if given cookies. Rarely fight and instead evacuate to caves with their parents. If a comrade dies, they soil themselves and flee crying, but since they are the slowest on the island, they almost never escape. Often bullied by Akagaga. Decent learning capacity and understands human speech. Once an individual dies, they do not respawn. They do not regenerate and do not get sick.

Average height: 70cm. Average weight: 31kg. Intelligence: Roughly that of a 4-year-old. The fourth most common variant, characterized by a pudgy, dumpy build. Likes fruits and fish; hates all vegetables. Can only say "Gugugaga" and cannot speak more than 20 characters. No concept of gender. A Gugugaga lifeform. They look down on humans and try to treat them like servants. If unhappy, they snap and punch with the force of a second-grader. When fighting, they attack with wooden sticks or bare hands. Though they've never seen a comrade die, they often continue fighting without caring about casualties. Being fat, they are "satisfying" to cut and have more durability than others, but they die instantly if shot even slightly with a gun. They often counterattack, but if they realize they can't win, they will try to intimidate you while crying. They have the highest combat power on the island, but since the baseline is so low, even an elementary schooler could win. Low learning capacity, but understands human speech. Once an individual dies, they do not respawn. They do not regenerate and do not get sick.