Nothing great.
The reason I gave it a humor rating was because of the voices. When I could hear them, they kinda made me laugh.
As a follow up to the review before mine...
Bass could also make easy work of Sigma by simply using the "Aquire Program" technique of his. In all essence, Sigma is a virus. He could be absorbed by Bass and use Sigma's power. That or use something simple like the Double Grave Cannon (not sure that's right).