I don't know which specific game or card game Yu-Gi-Oh zexal refers to. If I can provide more information, I will try my best to answer your questions.
3:10 to Yuma is purely fictional. It was created for entertainment purposes and doesn't draw from real-life events. The plot and characters were made up by the filmmakers.
Friendship is often a theme. The relationship between barian and yuma could be explored in terms of how they become friends or how their friendship evolves. It might involve them helping each other out in difficult situations, thus strengthening their bond.