check out our:
When I reflected on his crimes and malice, my hatred and revenge burst all bounds of moderation. I would have made a pilgrimage to the highest peak of the Andes, could I when there have precipitated him to their base. (9.6)
Okay, but question: is there such a thing as "moderate" revenge? Is revenge an emotion that you can even feel moderately—like, wanting a little revenge?
I, not in deed, but in effect, was the true murderer. Elizabeth read my anguish in my countenance, and kindly taking my hand, said, "My dearest friend, you must calm yourself. These events have affected me, God knows how deeply; but I am not so wretched as you are. There is an expression of despair, and sometimes of revenge, in your countenance that makes me tremble. Dear Victor, banish these dark passions. Remember the friends around you, who centre all their hopes in you. Have we lost the power of rendering you happy? Ah! While we love, while we are true to each other, here in this land of peace and beauty, your native country, we may reap every tranquil blessing--what can disturb our peace?" (9.8)
Victor’s guilt due to the deaths of William and Justine causes him to seek revenge against the monster.
All was again silent, but his words rang in my ears. I burned with rage to pursue the murderer of my peace and precipitate him into the ocean. I walked up and down my room hastily and perturbed, while my imagination conjured up a thousand images to torment and sting me. Why had I not followed him and closed with him in mortal strife? But I had suffered him to depart, and he had directed his course towards the mainland. I shuddered to think who might be the next victim sacrificed to his insatiate revenge. And then I thought again of his words -- "I WILL BE WITH YOU ON YOUR WEDDING-NIGHT." That, then, was the period fixed for the fulfillment of my destiny. In that hour I should die and at once satisfy and extinguish his malice. The prospect did not move me to fear; yet when I thought of my beloved Elizabeth, of her tears and endless sorrow, when she should find her lover so barbarously snatched from her, tears, the first I had shed for many months, streamed from my eyes, and I resolved not to fall before my enemy without a bitter struggle. (20.16)
Victor thinks that the monster's revenge is "insatiate"—that it'll never be satisfied. He's wrong. It will be satisfied, just as soon as he kills off everyone Victor has ever cared about.