Maria Robotnik (マリア・ロボトニック Maria Robotonikku?) is a character that appears in Sonic X. She was a young human, and the granddaughter of Professor Gerald Robotnik and cousin of Dr. Eggman. She was Shadow the Hedgehog's closest companion during his time onboard the Space Colony ARK. When GUN later shut down the ARK, Maria was killed when trying to assist Shadow in his escape from the colony.
Maria was a young slim human girl with shoulder-length blonde hair, peach skin and blue eyes. Her hair was wavy and held back with a blue hairband. For attire, she wore a blue crop top with short puffy sleeves and light blue trim, a pale blue long-sleeved dress and white low-heeled shoes.
Occasionally, Maria wore a dark pink hairband, a pink juliet sleeved dress with a white collar and a dark pink duel-flap tie, and dark pink flats with gray soles.
Maria was born on the Space Colony ARK. From birth, she suffered from an illness that made her body weak. As such, she could not leave the ARK and go visit Earth. Even so, Maria remained optimistic that she would recover.
During Maria's time, her grandfather, Gerald Robotnik, worked on a government project called Project Shadow. His research led to the creation of an immortal creature dubbed the "ultimate creature". His name was Shadow the Hedgehog, and Maria became close friends with him. Living together with Shadow onboard the ARK, Maria wanted to go down to Earth with Shadow and make new friends like him. Maria also took notice of Shadow's own interest in Earth and would hear his hopes of finding the meaning behind his existence on that planet.
Eventually, Maria's peaceful existence was shattered when GUN attacked the ARK in order to shut down Project Shadow and take possession of Shadow himself. During the violent raid, Maria and Shadow escape the GUN soldiers pursuing them and made it to the ARK's escape pods. There, Shadow got sealed inside one of the pods. While Maria was separated from Shadow however, she was spotted by GUN soldier, Mr. Schmitz. In an attempt to escape Schmitz, Maria ran back to the escape pods, where she prepared to deploy Shadow's escape pod. However, Schmitz caught up to her and warned her not to pull a lever. Maria ignored his warnings however, prompting a desperate Schmitz to shoot her. Mortally wounded, Maria, with her last strength, begged Shadow to help bring happiness to humanity for her sake, just before Shadow's capsule was jettisoned into space and Maria herself succumbed to her wound.
Maria's death was a jarring event that affected by Gerald and Shadow deeply. Upon learning of her death, Gerald went mad with grief and decided to take revenge on all of mankind by destroying the Earth with the Space Colony ARK. Shadow himself was likewise traumatized by Maria's death. In order to ensure his doomsday plan's success, Gerald brainwashed Shadow, twisting his memory of Maria's last request so that Shadow would be motivated to seek revenge at the human race.
Maria's last request for Shadow to protect the world and its people had a big impact on the hedgehog's future motivations, which Shadow made the promise to keep despite his loathing of humanity. When Shadow was reawaken nearly fifty years later though, he sought to avenge Maria's death (due to Gerald manipulating his memories) by destroying the human race. During his crusade, he met Christopher Thorndyke, whom he saw Maria in. It was later thanks to Chris' persuasion that Shadow remembered Maria's dying wish, prompting him to aid Sonic the Hedgehog and his allies in stopping the very plan he had set into motion, seemingly sacrificing his life in the process.
Maria was a peaceful and optimistic young girl. Despite her condition, she was not dissuaded from living her life and looked forward to the future in the hopes that she would recover and experience what the world had to offer. Having never been to Earth herself, Maria was likewise curious about what this planet was like and wished to go visit it and make friends. 
Maria was also a non-vindictive, very kind individual who always thought about others before herself. This is proven by the fact that after she was shot and was dying, she did not hold any ill will towards the people living on Earth, and in her dying breath, she requested Shadow to give them a chance to live happy lives.
Despite her youth and frailness, Maria was also brave and determined. Noticeably, she refused to heed a GUN soldier's threat when she tried to save Shadow. Even on her deathbed, Maria remained undeterred and only wished for Shadow to fulfill his purpose. She was also utterly selfless as she sacrificed her life for Shadow's sake, having faith he would carry on her dreams for her.
Shadow the Hedgehog
Maria's most prominent relationship was with Shadow the Hedgehog. The two of them were raised alongside each other onboard the Space Colony ARK and they formed a very close bond, with Maria considering Shadow a brother of sorts. Maria also shared the same dream with him which was to visit earth, making them kindred spirits in a sense, and they tended to look at the earth from the Space Colony ARK together.
- Christopher Thorndyke and Molly both remind Shadow of Maria because of their similar selfless natures and the kind, loving look in their eyes.
- Yoshimura, Kiyoko (21 December 2003). "Showdown in Space (Japanese version)". Sonic X. Season 2. Episode 38.
- Masaki, Hiro (30 October 2004). "Project: Shadow". Sonic X. Season 2. Episode 33.
- Masaki, Hiro (20 November 2004). "Shadow World". Sonic X. Season 2. Episode 36.
- Yoshimura, Kiyoko (27 November 2004). "Robotnik's Revenge". Sonic X. Season 2. Episode 37.
- Yoshimura, Kiyoko (14 December 2003). "Robotnik's Revenge (Japanese version)". Sonic X. Season 2. Episode 37.
- Yoshimura, Kiyoko (4 December 2004). "Showdown in Space". Sonic X. Season 2. Episode 38.
- Masaki, Hiro (7 December 2003). "Shadow World". Sonic X. Season 2. Episode 36.
- Houjou, Chinatsu (13 November 2004). "Sonic's Big Break". Sonic X. Season 2. Episode 35.