Galen Erso

Galen Walton Erso is a fictional character in the Star Wars franchise, appearing as a key figure in the 2016 film "Rogue One: A Star Wars Story". The character, played by actor Mads Mikkelsen, is a brilliant scientist and researcher with expertise in crystallography and energy enhancement, and is best known for his reluctant part in the creation of the Empire's Death Star. He is also the father of the film's main protagonist, Jyn Erso.

Galen was coerced into joining the Empire's cause by persuasive, and at times threatening, old friend Orson Krennic. They sought his genius in crystallography to harness the power of Kyber Crystals - powerful, Force-imbued crystals that were primarily used by the Jedi in their lightsabers. Krennic exploited Galen's research for the development of a superlaser, which would later become the primary weapon of the Empire's Death Star, a planet-killing battle station.

Galen, a pacifist and ethical man, however, was horrified when he learned of the Empire's true intention for his research. Deciding he could not stand by and allow his work to cause such devastation, he engineered a fatal flaw in the Death Star's design. This decision would later provide the Rebel Alliance with the strategy they needed to destroy the deadly battle station.

While working on the Death Star project, Galen sent a coded message to the Rebel Alliance about the weapon's weakness, which would, unfortunately, cause his death during an Alliance attack. His sacrifice, however, profoundly impacted the course of the Galactic Civil War in a way that brought the Rebellion a crucial victory and gave his daughter, Jyn, a cause to fight for.

Galen Erso's character arc symbolizes the struggle between duty and morality, and the costs and consequences of war. His choices and actions set into motion the events that lead to the downfall of the Empire, making him a consequential character in the Star Wars universe, despite his limited screen time.