User blog comment:Willbachbakal/My BioShock Sequel Idea Dump/@comment-1330314-20100506180647

Not exactly. I'm going to put in a few hints, as it's a bit hard.

Hint #1: Both weapons use highly advanced technology.

Hint #2: The Nail Gun replacement has something to do with light.

Hint #2: The Elephant Gun replacement is based on the works of Carl Friedrich Gauss.