Roberto Nicola is a playable character in Metal Slug Mobile 4, alongside Leona Heidern. He can be easily identified by his red hair. Roberto makes a second appearance in Universal Metal Slug: Tank Conspiracy, again joined by Leona. He is also a playable character in Metal Slug Team Mission, alongside Leona, Ralf and newcomer Nathalie.
A Regular Army corporal, Roberto admires Fio despite the overly cautious and clumsy nature of his superior.
He likes to help others out, though he is suspicious of helping out "good-looking women" as he became scarred after attempting to help Beatriz who subsequently froze him with her freeze gun. Roberto is also scared of zombies. He also claims that Amber gets along well with others despite her seemingly quiet nature.
When the Regular Army learns that a village is being constantly investigated by the Ptolemaic Army for red-haired men, Roberto is used as bait to draw the Ptolemaics out. He is immediately caught by Sally and Maria, though Maria knows he is not who they are looking for. Roberto panics over Sally's inextinguishable flames, but is spared when she decides to retreat. Due to being almost killed, he decides to dye his hair blue next time.
Roberto is assigned to serve under Fio, much to his delight. The two are tasked with delivering the Thunder Shot prototype. While driving, he finds a young woman on the side of the road and tries to help her. Instead, he gets frozen and Fio ends up having to wait for him to thaw out. Roberto later accompanies Fio in finding the thieves. He fights Allen Jr. and loses, but is saved by Fio. Roberto's assistance in recapturing the Thunder Shot allows him to meet the other members of SPARROWS.
He later goes on vacation so that he could spend time with Fio. However, he loses his ticket, and much to his dismay, buying another one costs too much so he ends up missing out on everything.
During Halloween, Roberto ends up babysitting Midori when the rest of SPARROWs abandon him to spend time at the Halloween party. When they return, they decide to prank him. Roberto becomes terrified by the sight of a zombified Tyra and Tarma before fainting. The next day, he reports the incident to Sophia.