Complex sentence: Vincent, Pesci and De Niro would go on to appear together in several other movies, his character almost always had an antagonistic relationship with Pesci's character, and one usually ended up killing the other.
Split into simpler sentences: Vincent, Pesci and De Niro would go on to appear together in several other movies. In most of their films together, Vincent's character would have an antagonistic relationship with Pesci's character, and one usually ended up attacking or killing the other.