Crono is the silent protagonist in Chrono Trigger. He lives with his mother in Truce in the Present. His personality matches that of the conventional hero archetype and he is willing to place his life on the line for the sake of others.
Crono was born sometime prior to 1000 AD to a woman named Gina and an unnamed father in the city of Truce. In his youth, Crono befriended a girl named Lucca. In the year 1000 AD, on the day of the Millennial Fair, Crono met Princess Nadia in disguise as Marle, though he did not know it at the time. Together, they enjoyed the fair's festivities until the unveiling of Lucca's new invention, the Telepod. Always faithful to his friend, he agrees to test the device despite the potential danger. The transportation was successful, however, when Marle wanted to tests it, she is sent back in time. Crono bravely decides to follow her, and the ensuing quest has him rescuing her lost ancestor Queen Leene to ensure Marle's existence in modern times. He, Lucca, and Marle all return to the present, after which Lucca suggests he escort Marle home, as she has work to do.
Returning Marle home back to Guardia Castle, he is accused of kidnapping her in attempts to thwart the throne. Represented by Pierre in a trial, Crono is sentenced to death by the Chancellor, regardless of whether he is found guilty or not guilty. Lucca frees him seconds before he is brought to the Guillotine and together, they flee the Prison Towers. On their way to Guardia Forest, Marle tags along and the three travel to the Future via an open Time Gate. Investigating the area in search of a means to return home, Crono and his friends find food supplies for the inhabitants of Arris Dome, where he also meets his descendant Doan and learns that the ruined future was caused by Lavos. He vows to save the planet from destruction through the use of time-travel. Shortly after, he assists a robotic robot named Robo in deactivating a Derelict Factory to find a way home.
while Entering the time Gate, he arrives at the End of Time where he receives magical abilities. With the aid of these powers and the powers of his allies, Crono successfully reforges the Masamune by acquiring Dreamstone in Prehistory and attempts to slay the Fiendlord, Magus, whom he believes is the root of Lavos's presence in the timeline. This leads him back to Prehistory where helps the Iokans destroy the Reptites, thus securing the evolution and prosperity of the human race whose lives were jeopardized by these sentient lizards. Directly afterward, he realizes Lavos was not summoned by Magus but is an alien species who fell from the sky in this time period. Attempting to follow the beast to the crater it created by landing, he is transported to the Antiquity era.
In the Antiquity time era, he rescues Melchior from the Mountain of Woe and subsequently attempts to rescue Schala, the innocent Zeal Princess who is being exploited by her mother, Queen Zeal. When Crono confronts Lavos in the Ocean Palace of the Kingdom of Zeal as a result of the rescue mission, he sacrifices himself to save everyone present. With time travel, his friends manage to replace him at the moment before he dies with a clone received from the Millennial Fair in 1000 A.D., saving his life. While the other six playable characters have many lines of dialog, Crono's responses to events are usually implied only through reaction and gesture, often for comedic effect, which wrongfully depicts him as insincere at the moment of his resurrection. Returned to normal, Crono and two others confront Lavos, destroy it, and return peace to Guardia. After, Crono travels back in time to rescue his mother who haphazardly stumbled into a Time Gate.
There are some points where he's shown to have strong romantic feelings for Marle. At one point where he's knocked out, he has a dream where Marle is his wife. The PlayStation, DS, and Windows versions of Chrono Trigger include an FMV scene at the end that shows Crono and Marle getting married. While a second FMV depicts the fall of Guardia Kingdom in the year 1005 A.D, it is unknown what happened to him during this event.
In the entire game, Crono never talks except in Ending 12: Memory Lane.
It is possible that he and Marle are still alive during the events of Chrono Cross, as Doan (Crono and Marle's descendent) still exists in the new timeline of the year 2300 A.D. although it's also possible that both of them died in the fall of Guardia, but were survived by any children that they may have had during their five years of marriage.
Chrono Cross
Crono's fate is alluded to in Radius's statement about the Kingdom of Guardia is no longer being peaceful. Like Marle, he is very likely alive as referenced in Lucca's letter about her friends. Three times in this timeline, a version of him appears as one of the Ghost Children along with Marle and Lucca. The first time, he states that the future in which Earth is ruined by Lavos is going to be brought back into being due to the interference of Serge, who caused the Home World and Another World split. The second time is in an illusory space at Terra Tower, in which Belthasar enlightens Serge's party about some of the affairs of the Dragons. Crono's final appearance in Chrono Cross comes immediately before the final battle of the game. Crono tells Serge that Wazuki was turned into Lynx by FATE, and along with his fellow "Ghosts," the other two members of the original time-traveling group, implores Serge to destroy Lavos once and for all.