"Senior, I'm curious about something."
"Speak!"
Xiao Yun looked at Lei Zhan across from him and asked in confusion, "I clearly already owe you a huge favor. In the future, if I truly manage to subdue that Imperial Weapon and you want to borrow it for a few days, I definitely won't refuse. Why do you still want to make a deal with me?"
Lei Zhan smiled faintly. "That is different. Back then, although I would also be able to borrow your Imperial Weapon, I would have to use up the favor you owe me. But now, this is a fair trade, and you still owe me a favor."
Xiao Yun froze, then broke into a bitter smile.
The older the ginger, the spicier it was!
Damn it, this old fellow was far too shrewd.
"Kid, do you have any guesses about the remaining two Sword Daos?" Lei Zhan changed the subject and asked with a smile.
Xiao Yun pondered for a moment. "I think these remaining two Sword Daos should be fundamental elements of heaven and earth as well, like earth, fire, water, wind, and lightning. So my guesses are metal, wood, life, death, extreme yin, extreme yang, and so on."
Lei Zhan nodded approvingly, then shook his head with a smile. "The fundamental elements of heaven and earth are not limited to those. There are two most important ones that you have overlooked."
"Oh? Which two?" Xiao Yun's eyes lit up as he looked at Lei Zhan. He knew these two had to be the Sword Daos he needed.
"Time and space!"
Lei Zhan's expression turned solemn as he said in a deep voice, "Time and space are the most powerful and most fundamental elements in this world. One could even say that a world may lack metal,