A Fistful of Dollars

A Man with No Name (Clint Eastwood), arrives at a little Mexican border town named San Miguel. He is quickly introduced to the feud between two families vying to gain control of the town: the Rojo brothers, consisting of Don Miguel (Antonio Prieto) (the eldest and nominally in charge), Esteban (Sieghardt Rupp) (the most headstrong) and Ramón (the most capable and intelligent, played by Gian Maria Volontè, who would reappear in For a Few Dollars More as the psychopathic El Indio), and the family of so-called "town sheriff" John Baxter (Wolfgang Lukschy).The Stranger quickly spies an opportunity to make a "fistful of dollars" and decides to play both families against each other. His opportunity comes when a detachment of Mexican soldiers escorting a shipment of gold passes through the town. The gold is ostensibly being delivered to a troop of American soldiers at the border river in exchange for a shipment of modern American weapons, but upon following the Mexican troops, the Stranger watches from hiding as they are massacred by members of the Rojo gang, disguised in American uniforms and led by Ramon Rojo.The Stranger takes two of the bodies to a nearby cemetery and sells information to both sides that two soldiers survived the attack. Both sides race to the cemetery, the Baxters to get the "survivors" to testify against the Rojos, and the Rojos to silence them. The factions engage in a fierce gunfight, but Ramon manages to kill (as he believes) the "survivors" and Esteban captures John Baxter's son Antonio. While the Rojos and the Baxters are busy, the Stranger takes the opportunity to search the Rojo hacienda, but accidentally knocks out Ramón's beautiful prisoner and unwilling mistress Marisol (Marianne Koch) when she surprises him. He takes her to the Baxters, who arrange for a prisoner swap with the Rojos.The day of the exchange, the Stranger learns Marisol's history from Silvanito (José Calvo), the innkeeper: "... a happy little family until trouble comes along. And trouble is the name of Ramon, claiming the husband cheated at cards, which wasn't true. He gets the wife to live with him as hostage." That night, while the Rojos are celebrating, the Stranger rides out and frees Marisol, shooting the guards and wrecking the house to make it look like it was attacked by a large band. The Stranger tells Marisol, her husband and their son to leave town, and gives them some money to live on. Marisol then asks the Stranger, "Why do you do this for us?" And for the first and only time, the Stranger provides some insight for his actions when he replies to Marisol, "Why? Because I knew someone like you once. There was no one there to help. Now get moving."The Rojos capture and beat the Stranger up after this betrayal, but he escapes, killing Chico (Mario Brega) in the process, with the help of the coffin maker Piripero (Joseph Egger, who would also resurface in For a Few Dollars More). Believing the Stranger to be protected by the Baxters, the Rojos set fire to the Baxter home and massacre all the residents when they are forced to flee the flames, including John Baxter, his son and his wife Consuelo (Margarita Lozano). The Rojos become the only gang left in San Miguel.The Man with No Name returns to town to engage the Rojos in a dramatic duel. He first rescues Silvanito, who was tortured to reveal the Stranger's whereabouts. The Man with No Name has a steel chest plate hidden under his clothing and taunts Ramon to "aim for the heart" as Ramon's rifle shots bounce off. The Man with no name then challenges Ramon to reload his rifle faster than he can reload his pistol. He shoots and kills Ramon and the remaining Rojos, except Esteban (who is shot by Silvanito), and rides away.

Question: Who massacres the Mexican troops?
Answer: The Rojo brothers