Sanda's name is derived from the Japanese word for 'mountain', (サン?), reflected by the fact that he has spent his life living in the mountains. It could also be derived from the Japanese word for 'three', which is also san. This may relate to his status as the third 'Frankenstein monster' to make an appearance, after SanFrankenstein himself and Gaira.
Sanda resembles his "brother" Gaira, being a humanoid giant covered in fur. He is also significantly bigger than Gaira. Unlike Gaira, Sanda has a more human-like face, and has what appears to be a beard on his chin. Sanda's fur is a light brown color. In Go! Godman, Sanda's suit has heavily decayed and most of the hair on his body has fallen off, while the hair on his head is much longer. In the follow-up series, Go! Greenman, Sanda's suit is still decayed, but his head has been replaced with a more ape-like head.
In War of the Gargantuas, Sanda is gentle and caring, due to being lovingly raised by human scientists, including Akemi Togawa, when he was an infant. After learning that his "brother," Gaira, is under attack by the J.S.D.F., Sanda rescues him, but does so non-violently, refusing to fight back against the military. Sanda tries to keep Gaira safe and allow him to recuperate, but grows angry when he learns that Gaira is attacking and killing humans. When Gaira attacks Tokyo, Sanda decides he is willing to kill his own brother rather than let innocent humans die.
In Godzilla: Rulers of Earth, Sanda retains most of these traits. Sanda has desperately been searching for Gaira, and follows him to the Pacific Ocean after Gaira escapes from a Chinese military facility. When Sanda finds himself surrounded by military forces after coming ashore in Australia, he surrenders and refuses to fight them. When he sees Gaira willingly destroying the military forces, he becomes distressed and tries to stop his brother. Despite this, Sanda has a strong loyalty to Gaira, and will do whatever he can to protect him without endangering human lives.
In War of the Gargantuas, Sanda is believed to be the result of some of Frankenstein's flesh breaking off in the mountains of Japan. Over time, this severed flesh grew into Sanda, who was discovered by scientists. As a child, Sanda was raised in a research facility under the care of Akemi Togawa. Eventually, Sanda escaped and returned to the mountains, where he grew to 30 meters in height. Due to his upbringing, Sanda became a gentle and kind creature who had a positive view of human beings.
Sanda grew from the flesh of Frankenstein, along with Gaira. He was captured by scientists and studied when he was small, but he escaped to the mountains. One year later, he had grown to 30 meters in height. He returned to save Gaira from the J.S.D.F., and he took him to the mountains. Gaira started to eat humans, which angered Sanda, due to his upbringing around people. Sanda attacked Gaira, but Gaira fled. Gaira attacked Tokyo, and Sanda fought him again. They fought in the sea, but they were both pulled into a volcano.
- Sanda is a capable hand-to-hand combatant, and in Godzilla: Rulers of Earth demonstrates the ability to use improvised weapons.
- Sanda appears to have human-like intelligence.
- Like his brother, Sanda displays enhanced regeneration, being able to completely grow back from just a few of Frankenstein's cells.
- In Go! Greenman, Sanda can breathe a very toxic mist from his mouth.
- In Go! Greenman, Sanda can alter his size after Tonchiki casts his trademark magic spell.
ComicsGaira and Varan flew into the distance. At some point, the brown Gargantua gave chase and dove into the ocean which the two brawling monsters landed. Sanda chased his enraged brother, over a severely angered Godzilla, who followed the two. Sanda was knocked out off panel, and came to, surrounded by military. Suddenly, Gaira dove onto him, but to protect him from Godzilla's beam. The green gargantua then hurried to keep his injured brother safe, smashing a tank that almost shot the brown giant. This angered Sanda, and the two had a small fight, only to have it broken up by another heat beam. The two brothers worked together to fight Godzilla, until Sanda smashed a Saradian petrol tanker over Godzilla's face, causing the monster king to retreat. Gaira, now knocked out and injured, was protected by Sanda, and the two were transported to the new Monster Islands. There, Sanda lived with his brother alongside Baragon, Kumonga, Rodan and Zilla. At one point, Sanda was seen battling Kumonga alongside Baragon. When the Trilopods attacked the Monster Islands, Sanda was getting strangled by a Trilopod with Kumonga's traits, only to be saved by his green brother.
However, Sanda and his brother were eventually captured by Trilopods and had their characteristics copied, and while their Trilopod clones went to fight Godzilla in Los Angeles, Sanda and Gaira were kept in the Trilopod hive, until King Caesar broke all the Earth monsters free. Sanda, along with every other monster captured in the hive, rushed to fight the Trilopod swarm, and then tried to attack Magita when the massive Trilopod appeared, only to be swatted to the side. When Godzilla destroyed Magita, Sanda and every other monster present followed the monster king into the ocean.
- Main article: Sanda/Gallery.
- Sanda's appearance in Godzilla: Rulers of Earth, as he runs away from a helicopter, is an homage to Robert Patterson's Sasquatch film. Much like his brother, Sanda does not appear in the 'Natural Balance' of the five elements of Monsters.
- Sanda is very similar personality-wise to the monster that spawned him, Frankenstein. Due to being raised by humans, both monsters are gentle towards humans, and risk their lives to battle monsters that threaten humans.