It’s still unclear exactly what the shooter in Las Vegas used to carry out his disgusting attack last night. By all accounts, he had so many weapons that it’ll be a while before we know which ones he chose. Nevertheless, two new pieces of evidence have come to light in the last few hours, and both give us a little insight into who he was and what he was hoping to achieve. The first piece of news is that the killer “passed all required federal background checks” on at least two recent occasions: