I wanted to post something here because it hasn't been used in a while and it is such a fun concept.
Depending on the increasing popularity of UY, I would imagine that Screw Attack will probably make a Death Battle between Usagi and Samurai Jack. How do you think it would go down? Admittedly, I watched Samurai Jack routinely as a child but don't know the whole story.
The physics of the UY world and Samurai Jack's world may be slightly different btw. I really think they need to consider such things in Screw Attack. Physics in one reality do not equal physics in another. Thus, there has to be some sort of regulation - which would mean more focus on technique and skill...but then again, inherent freakish traits transcending conventional physics do seem to be regular explanations of superiority in many comics/manga. That's why it's so hard to say x character would beat y character.
Anyway, the UY world I'd say is roughly the same physics as earth - just with different evolution leading to certain features such as increased speed and jumping ability. Which would explain why Usagi is so fast and can jump high (he's a rabbit lol). Although, there are Yokai and magic so it's not completely like earth.