Complex sentence: Antony verbally agrees to join Octavius and even signs a document stating that Octavius has the support of his troops should he die; however, Octavius makes the naïve mistake of offering Antony leadership if he himself should perish.
Split into simpler sentences: Antony verbally agrees to join Octavius and even signs a document stating that Octavius has the support of his troops should he die. However, Octavius makes the naïve mistake of offering Antony leadership if he himself should perish.