Generally just makes the Kitten crazy to run around with.
Also a new barrel because why not.
Some of the changes are, but not limited to:
More Damage, faster firerate, splash damage...
And no more of that ridiculous spread
(If you want that back, just get rid of the line that contains 'FiringPatternLines ()')
I know it doesn't really need it, but that doesn't mean it won't be fun.