Interestingly, one anime called Darker than Black does the more realistic option and the super speed guy runs into rain and the raindrops are like bullets on his skin because he's not super durable. That's the difference "minute" physics changes can bring. Also, it would be good if it was so interesting of a concept that people would be trying to read more about the finer details.

[quote=@LeeRoy]
[@ImportantNobody] Infinite Speed.

You do realize you would literally tear a hole in reality with something like that.

You would break down physics on a fundamental level with literally infinite energy.

Also, how does a character even GET infinite speed beams?
[/quote]
I realize that, that's why I said that. :p

Infinite speed beam guy got it through training for a couple minutes or something because he has swag. He's one of the most powerful in the multiverse.

For my multiverse I'm going with the "the magical energy doesn't interact normally with mundane physics" option so infinite speed doesn't mean infinite attack power and energy.