Silvio Morello is a guerrilla who calls himself Yara's biggest Rambo fan, and he gives the Rambo crossover mission All The Blood. Finish it and you walk away with the Rambo bow.
All The BloodAll The Blood is a free Rambo crossover mission. A Rambo superfan who collects memorabilia asks Dani to take out FND Colonel Tizel in true Rambo style. You earn Rambo's Vengeance Bow.Silvio is a big-hearted, not very competent fighter who lives for Rambo films. His grudge with Tizel probably goes back to his failed army training, while Tizel rose to colonel.
Silvio asks you to kill Tizel Rambo style. After that, you fetch a key that opens a hidden box at Fort San Miguel holding the bow. The mission then has you use the bow on a set number of soldiers before it is yours to keep.