A mysterious artifact found in the Dark Ruins near Glory City. It's appearance is that of a black jade pot with a sparkling and translucent, with gem-like shine on it. It dates back to the Snow Wind Empire Era and is said that it was found in an ancient tribe.
Nie Li was able to acquire the Nightmare Demon Pot at the treasure auction held at the Hong Yue auction house. It was the last item put up for bid and was fierce competed over. Nie Li asked Yang Xin (director of Alchemy Association) to win the auction no matter what. Eventually she bid, 120,000,000 demon spirit coins and defeated a mysterious grey robed man that was also bidding high. Nie Li offered to repay her, however she declined it when he said that the Nightmare Demon Pot was a gift for his "master."
Nie Li initially only knows one of its uses, which is refining demon spirits. By putting in ten demon spirits of the same attribute, there is a chance of a more power demon spirit forming. If one is lucky, there is a possibility for a rare demon spirit. However, there is a risk of all the demon spirits being destroyed. The chances of a rare demon spirit or a complete failure are both rather small. The majority of the time it just forms a slightly stronger demon spirit. The higher the level of the demon spirits being refined, the higher the chance at failure.
Nie Li is primarily looking for a demon spirit with a high growth rate. With this, even if the demon spirit starts out weak it will greatly improve with effort. As he uses the demon pot to refine demon spirits, he tests their growth rate with a soul crystal. Nie Li also notices that the Nightmare Demon Pot was absorbing a small portion of the power from the refined demon spirits. As time went on, the Nightmare Demon Pot is becoming stronger with the failure rate decreasing.
After refining god level growth rate demon spirits for himself and all of his friends, Nie Li didn't use it again until going to the Draconic Ruins Realm. After having little to no opportunity to gather Spiritual Stones, Nie Li decides to use the Nightmare Demon Pot to make god level growth rate demon spirits to sell. However, he is extremely cautious and did not reveal the pot's existence to anyone, even his close friends as the Nightmare Demon Pot's ability makes it a priceless treasure that others would kill Nie Li and his friends for.
When Nie Li started to refine the dragon bloodline demon spirits in the Nightmare Demon Pot it had a strange reaction. It started to glow scarlet red and a mysterious pattern gradually formed on its surface. The design looked like a dragon with its wings spread wide. After refining thousand of dragon bloodline demon spirits the aura of the Nightmare Demon Pot grew stronger and the pattern became more distinct. This is a sign that the pot had upgraded, improving its success rate among other things.
Another strange thing occurred when some of the demon spirits started to mutate. Usually, there’s a set probability to whether or not a demon spirit will mutate upon ranking up. However, these particular demon spirits had mutated during the fusing process instead. This is a new effect of the Nightmare Demon Pot. When regular Dragon Bloodline demon spirits are refined with a mutated one, the success rate is much lower. However, the results are much better when it did succeed.
While pouring his energy into the Nightmare Demon Pot to keep the final two extraordinary level dragon bloodline demon spirits fusion from failing, Nie Li discovered that within this mysterious artifact was a huge space that contained boundless Heavenly Energy, like a vast ocean. It was in this ocean of energy that Nie Li was able to gain the enlightenment to reach the Heavenly Fate Realm.
After Nie Li acquired the Myriad Miles Rivers and Mountains Painting he placed the Nightmare Demon Pot inside it as the space was able to nourish and strengthen other divine artifacts. In the future he always refined demon spirits within this space also.