El Dorado is a new character introduced in Metal Slug Attack.
He is a billionaire who lives in the Sand Kingdom. At some point he invented an armored suit powered by plasma and equipped with a high-powered jet engine; this helps him protect the Sand Kingdom from criminals.
El Dorado first appears in the Extra Ops "Golden Soldier", where he repels an attack by Abul and his lackeys, who use the Assy Nero. El Dorado soon takes custody of Abul to face judgement for his crimes against the Sand Kingdom.
El Dorado first appears in "The Sand Kingdom and the Golden Hero", where he travels around the Sand Kingdom to protect its villagers. He helps Eri and Fio repel the Rebel Army from the Sand Kingdom before taking custody of Abul Abbas.
Later on in "Cleopatra's Pleasure Tour", he hits on Cleopatra, initially believing her to be a cosplayer since no one had heard from her in millennia. When he witnesses her power against the Rebel Army, he realizes that she has returned and accompanies the group as a loyal servant to avoid angering her. He repairs a broken Big Gate and when Cleopatra and her mummy servants enter, he wonders if he should have gone with them before deciding against it.
- He is heavily based on the Marvel Universe superhero Iron Man.
- His suit is an edited version of the Slug Armor.
- El Dorado is a Spanish term for "the golden one" which briefly explains why he proclaimed himself as a golden person.