Bakusou Senki Metal Walker GB - Koutetsu no Yuujou (Japan)

About

Metal Walker takes place late in the 21st Century when a valuable and evolving metal known as Core is discovered on an island. Military leaders sought to use Core to develop weapons, but an accident turned the island into a ruined wasteland. The Rusted Land, as it is called, is where the game takes place. Because of the research, the island is scattered with malicious robots known as Metal Busters.[4] Fifty years after the accident, the main character and his father Tetsuo Kurama have devoted their lives to search for lost Core Units on the island, but the game opens as the father is separated from his son as a gang of Metal Busters attack. The main character and his Metal Walker, Meta Ball, must then search for his father on the island.[2] Professor Hawk, Tetsuo's employer tells the main character that his father will be found where there are Core Units, so he then goes to seek them out.