Complex sentence: The songs "Silver Dagger" and "Drowsy Sleeper" have some relation to each other, but differs in lines, verse rhythm and outcome, and at some point there might have been a fusion of two different songs.
Split into simpler sentences: The songs "Silver Dagger" and "Drowsy Sleeper" have some relation to each other, but differs in lines, verse rhythm and outcome. However, at some point there might have been a fusion of these two different songs.