I know that in the tenth line I have one more syllable than allowed in a sonnet. I cannot think of how to change it.

A war inside the mind of good Brutus.
Noble and true and righteous, yet modest
He must choose between Caesar and Cassius.
His intentions though brutal were honest.
Caesar, his friend about to become king.
"Hail mighty Caesar!" Rome's people rejoice
Yet fear is what horror Caesar may bring.
Noble Brutus must now make a hard choice.
Brutus, he chose Rome and slew his best friend.
"Et tu Brute?" Caesar cried, "Then Caesar fall!"
Brutus knew not war was around the bend,
And that he would join Caesar in his death.
Brutus lost the war and with a long sigh,
He realized like Caesar, he too must die.