Slap you with money
John stood silently as he thought of which of his skills he could offer up. Someone with his life experiences was not lacking in personal skill or ability, but he had to pick the right one. Lex waited patiently for him as the man ruminated. Even if Mary hadn't told him to give John a chance, he would have. He wanted to learn more about this person that even the System couldn't identify. He was more than sure that 'John' was just an alias and was not this man's real name.
Finally the man decided and said, "I have extensive knowledge about various cultivation techniques and styles. I can custom create spirit techniques for your guests based on their cultivation. It will be a technique that suits them the most."