Here are some specific arguments for each side:
Victor is the real monster
* He created the creature and is therefore responsible for its actions.
* He abandoned the creature after his creation, leaving him to fend for himself in a hostile world.
* He is willing to sacrifice the creature's life in order to protect his own.
The creature is the real monster
* He is responsible for the deaths of several innocent people.
* He has a violent and destructive nature.
* He is unable to control his emotions and often acts impulsively.
Ultimately, the question of who is the real monster is left up to the reader. However, Mary Shelley's novel provides a thought-provoking exploration of the complex relationship between creator and creation, as well as the nature of good and evil.