In Metal Gear Solid V: The Phantom Pain, the child soldier who becomes a rival to Venom Snake is Eli.
Eli is introduced as the leader of a group of young fighters in Africa. Although he is still a child, he displays exceptional confidence, combat ability, and hostility toward adult military organizations. His identity and behavior connect him to major revelations about the broader history of Big Boss and the evolution of the series' recurring characters.
Players sometimes confuse Eli with Liquid Snake because the game deliberately presents links between them. Eli is not simply an adult version of Liquid Snake, however; he is the child character whose later history leads toward the identity known from the original Metal Gear Solid. His relationship with Venom Snake is therefore both personal and central to the series' chronology.