Reaching the Heaven-Dao Nascent Soul stage... was supremely difficult!
That difficulty lay in the fact that not only did one have to get five deva souls, but each of those souls also had to represent a different one of the five elements. Metal. Wood. Water. Fire. Earth. Only with a complete set could one succeed. It really was a very difficult matter.
In the lands of Heavenspan, deva souls were very rare, and it was only by chance that Bai Xiaochun had begun to collect them. He had been given one in the Spirit Stream Sect, and then gifted one by Du Lingfei. However, it was only when it came to the third soul that he had been forced to work hard to get it.
After putting his life on the line, he got the third soul in the labyrinth, after which he had been teleported deep into the Wildlands. Then, to get his fourth deva soul, he had risked everything, and also offended the Bai Clan!