Mario felt an interesting cocktail of emotions at being so bluntly accused. At first, he felt amused and that this tavern owner was very interesting. He'd been in Babylon for so long that he had pretty much established the list of people who he should not cross, and it had fewer people than one would assume.
Then, however, he felt caution and apprehension. Lex had used some strange method to trap all the troublemakers, and Mario had not been able to sense what it was. But then his experienced mind got to work, and he calmed down, and in fact, looked at Lex in an admiring light.