Wuxia Crossover: From the Start, I Sell the Sunflower Manual to Dongfang Bubai

Qin Nanxuan transmigrates into a world of combined martial arts and obtains the Jar Shop System. Every jar he sells earns him a matching reward. Dongfang Bubai visits and opens a jar containing the complete Sunflower Manual, advancing to Grandmaster rank on the spot and becoming the shop's first devoted customer. Word on the streets is that the jars here can yield peerless martial arts manuals, or even a Gatling gun capable of wiping out an entire sect.