Mountain range
As the hours passed by, and Lex came nearer to the castle, the aura grew stronger. While it was well within the range that Lex and Fenrir could tolerate, Lex found it interesting that the assassins also remained unaffected. As a subsidiary race of the dragons, weren't the Frigals supposed to be even more vulnerable than others to this aura?
Based solely on what he saw, that did not seem to be the case.
As the hours wound by, another question took hold in Lex's mind. What was 'aura' exactly? He himself had an aura, and more than one. The first and most obvious aura was that of the Innkeeper, but that originated from his Host Attire. It gave others great mental pressure, and within the Crystal realm even affected the environment.