Complex sentence: Martin is Oscar's childhood friend alongside Kate and tries to help them uncover the secret of Providence using his intellect, however he is also a coward and prefers to stay away from trouble and direct confrontation with the series' villains as best as he can.
Split into simpler sentences: Martin is Oscar's childhood friend alongside Kate and tries to help them uncover the secret of Providence using his intellect. However, he is also a coward and prefers to stay away from trouble and direct confrontation with the series' villains as best as he can.