As Samus's new ship falls into the atmosphere, she could feel atmosphere burn up her ship. Ridley must have damaged her ship's deflector sheilds. It was going to be a rougher landing than she thought. Samus braced for impact.
A few days later, an unconscious Samus woke up in a medical facility. She was confused, because she thought she was on a ship. Two bird-like people were moderating her vitals. "Where am I?" She asked. The bird-people responded with an understandable, but still confusing language. They told her that they found her unconscious, bleeding on a ship.
They told Samus that they would give her a choice: either heal naturally, or she could undergo some experiments to make her stronger and heal faster. Samus, being young and not really understanding how choices affect her, she said that she would like to heal faster.
They brought in their strongest, most powerful and capable warrior, gray voice, and had him donate blood. From there, the Chozo did a blood transfusion, making Samus stronger.
They then decided to raise Samus, after learning of the death of her parents, and taught her how to fight. They also taught her how to make repairs to ships, fixing her ship in the process, how to heal people medically and how to do it without any medical tools, and how to fly a ship, taking her for test drives over the planet.
By the time she became 18, she could take down almost anyone. So, for her final trial, Gray voice was going to fight her. Once Samus was ready, they would give her a power suit meant to be like the the tough skeleton of the Chozo. It came with a arm cannon, which could shoot a beam, stun others with an electric pulse, and shoot some plasma balls. Samus was ready for her final trial.