The (failed) attempt at intimidating the flies that attempted to harass Francis, which was the reason why Flik even mistakenly believed they were warrior bugs in the first place, was a spoof on Robin Hood. Also, after they demolished the bar in their attempt to flee, Francis pulls Slim out in a parody of King Arthur pulling out Excalibur. The music that plays in that scene sounds similar to the Master Sword theme from The Legend of Zelda.