Rubem was a leader of a militia trying to guard a specific region that the party and the expedition crew they were with crossed into. Unfortunately for him and his troops, the party were vastly more powerful, and the fight ended with hardly any injuries on the expedition side. Double unfortunately for him, he was the last man standing of his group, and the expedition knew they couldn't let him get away with the knowledge they were entering the region, so the last thing he did before being executed was smoke a cigarette. Not the most dignified death, but it was better than Pedro who died minutes earlier in the same conflict.