He and that chainsaw have a prior moment by using a storm-propelled shark's inertia to cut it cleanly in half.
A tornado full of sharks. How is that NOT awesome?
Nova is pretty much a walking Moment of Awesome when you consider that, if you count the bombs thrown into the tornadoes, she has the highest kill score of all of the main characters. Even if not, her proficiency with a shotgun more than qualifies her.