Castle of Black Iron

It was still half a month away from the time when the tower of time in the demons' secret realm in Mountain Ruins would be available. However, it would take Zhang Tie at most 2 days to arrive there from the core region of Mountain Ruins, including the period during which he passed through those deities' battle puppets. Therefore, Zhang Tie had more than ten days to check his ideas.

He did it right now.

As it was empty in the Heaven of Light, nobody disturbed him at all. Zhang Tie then entered Castle of Black Iron with excitement and showed up in the lobby of the Palace Tree immediately.

Those women of Yin-Yang Sect were fully immersing themselves in a great job——arranging those people whom Zhang Tie saved and moved into Castle of Black Iron outside the Immortal Mountain. Even Agan, Edward and Aziz were helping them over there. As a result, the Palace Tree became tranquil. Only Heller was there.

The space ball of Motian Realm and Nine-Heavens Immortal Spring were both in the lobby of the Palace Tree.

Floating in the air, the space ball matched the lobby of the Palace Tree very well. So did the Nine-Heavens Immortal Spring. With Nine-Heavens Immortal Spring and Immortal Stone, the lobby of the Palace Tree became vigorous. All the body parts of fierce deities were stored in the underground garage beneath Palace Tree.

"Welcome back, Castle Lord..." Heller greeted Zhang Tie with an elegant bow as if he had already guessed Zhang Tie's intention. After that, he stood under the high platform of the small tree and watched Zhang Tie with an anticipated look.

"Hahaha, Heller, I appreciate you so much this time..." Zhang Tie laughed as he came under the small tree with a flash.

"Castle Lord, you should think it all by yourself. I'm just your butler and can assist you to manage Castle of Black Iron. I don't know anything. Neither did I say anything!" Heller said as he shrugged while talking to Zhang Tie with a solemn look.

"Heller, I find that you're very cute now..."

"Erm..." Heller became speechless.

Rubbing his hands, Zhang Tie circled around the small tree with great excitement as he thought about the next step.

——which should come first, apply fertilizer or water?

After circling around the small tree for a short while, Zhang Tie slightly recovered his composure. After that, he decided to try the small tree's response to Nine-Heavens Immortal Spring first. Step by step!

This process was like growing flowers and trees. All the flowers, grass and trees needed watering. They adapted to water the most. Therefore, Zhang Tie decided to try the small tree's response to Nine-Heavens Immortal Spring first. As for whether the body parts of fierce deities could become the fertilizer and be absorbed by the small tree or not and whether they were beneficial or harmful to the small tree after being absorbed, it was unknown. Perhaps it was just his conjecture. He would try the effect of the fertilizer after Nine-Heavens Immortal Spring.

Therefore, Zhang Tie ran his spiritual energy. Only by waving his hand, a stream of water had flown out of the pool of Nine-Heavens Immortal Spring like a fountain and crossed the sky like a water bridge before entering the soil where the root of the small tree was.

In the beginning, Zhang Tie only watered about 500 ml Nine-Heavens Immortal Spring, which was only equal to a bottle of water. Zhang Tie thought it was not too much.

The soil was a bit special. Zhang Tie had found that the soil was special a long time ago. It looked dark brown and nothing different than ordinary soil; though, it was very odd. When he slightly grabbed the soil, he could take it like taking ordinary soil. However, when he grabbed it forcefully, he found the soil would become even harder than iron.

The Nine-Heavens Immortal Spring entered the soil immediately.

Standing beside the small tree, Zhang Tie was observing the small tree's response with wide eyes.

One minute later, the small tree didn't make any response.

Two minutes later, the small tree still remained unchanged.

Five minutes later, the small tree didn't change at all.

'Is Nine-Heavens Immortal Spring useless to the small tree or the Nine-Heavens Immortal Spring is not enough?'

When Zhang Tie muttered, he found that a small leaf in front of him suddenly moved a bit. Closely after that, the leaves around that small leaf also moved. Then, all the twigs and leaves started to move with rustles which sounded like a spring breeze blowing over beautiful aeolian bells. What a piece of euphonic music! In an instant, the entire Palace Tree reverberated with the euphonious sound from the leaves of the small tree.

The small tree was singing jubilantly. Additionally, a faint rainbow-like light appeared over the trunk and each leaf of the small tree. Meanwhile, Zhang Tie saw new leaves growing out of the ends of the twigs.

Zhang Tie became this ecstatic.

'Nine-Heavens Immortal Spring is really useful to the small tree. It seems to be very useful to the small tree!'

The small tree's change lasted for almost 10 minutes. When the small tree's song gradually sank and the rainbow-like light slowly turned weaker, Zhang Tie waved his hand towards Nine-Heavens Immortal Spring in the far. Closely after that, a stream of spring water flew over there and fell on the root of the small tree. In an instant, the small tree's jubilant song went louder; meanwhile, the rainbow-like light over the small tree became brilliant again.

Being watered by the Nine-Heavens Immortal Spring, the small tree started to change. Many new leaves and twigs grew out. As the small tree was covered with more and more leaves, its twigs grew longer; even its trunk grew thicker and higher. Meanwhile, the small tree was gradually growing higher and bigger.

After consuming almost half of the Nine-Heavens Immortal Spring in the pool, the soil finally became saturated. Therefore, Zhang Tie stopped watering it.

At this moment, the light that the small tree gave out was so strong that Zhang Tie couldn't even open his eyes. The entire small tree was covered with brilliant light. Even Zhang Tie was forced to jump away from the small tree which was growing bigger.

The entire lobby of Palace Tree was filled with brilliant light, euphonious sounds and various odd fragrances.

The small tree's change lasted for a whole day. After the brilliant light disappeared, a 10-m higher big tree whose crown was like a cloud appeared in the lobby of Palace Tree. Additionally, there was a very eye-catching fruit on the big tree which was giving out brilliant golden light...