Ryley Robinson is the main character in the game "Subnautica". He crash lands onto the planet "4546B" in the "Alterra" Capital Ship, "Aurora".
He survives on 4546B by gathering resources, such as the scrap metal from the crashed Aurora and turning it into titanium with his "fabricator".
He finds out he is infected with a virus known as "Kharaa (Mongolian for "curse")". He also finds out that the Quarantine Enforcement Platform shot the Aurora down. He attempts to shut it down to escape but he finds out he need to cure himself of Kharaa.
He finds the Sea Emperor Leviathan, hatches her babies and cures himself, causing The Sea Emperor to die. He deactivates the QEP, builds the rocket and escapes.
At the end, he pays 1 trillion "credits (Alterra currency)" and lands. What happens after is unknown.