"Good sword!" Gu Cheng couldn't help but admire, in his opinion, this kind of casting level, even if he has some awareness with his father, but it has already been counted as everyone's work, this Master Yi really deserves the name of Tianyan City Casting Master.

"Master Yi, your casting level is really not good, the perfection of this sword really opened my eyes. ”

"Haha, little brother Gu is falsely praised, it's good to be worthy of his heart, but when it comes to perfection, isn't there still a lot of heat?" Master Yi glanced at him deeply, and there was a sudden flash of heat in his eyes.

Gu Chen smiled knowingly, how could he not know what he was thinking, this sword can only be considered truly perfect after it is integrated into Tiangang cold iron.

"Whew, okay, without further ado, let's get started. ”

Afterwards, he asked Lu Qi to arrange a quiet room for him, and asked everyone to stop what they were doing, and asked him not to make a little noise during his forging.

Lu Qi didn't dare to slack off on his request, but Master Yi on the side, although he wanted to see this sword mastery with his own eyes, but after Gu Chen politely declined, he also knew that such a casting was extremely laborious, and he couldn't tolerate the slightest disturbance during the period, so he didn't insist.

Holding the black sword in his hand, Gu Chen immediately plunged into a room in the far corner, closing the door tightly.

This room is only about three feet wide, but it is unusually neat and clean. In the corner of the room, there is a small bed cast of pure iron, and next to the bed, there is a long iron table, on which many daily utensils are neatly placed.

This room should be a special place for people to rest, and the faint smell of Lan Zhi's fragrance from the air, Gu Chen also knew that this must be the room where Lu Qi usually rests.

"This little girl loves to be clean very much. He shook his head and smiled, then turned his attention to the iron sword.

The palm of his hand was turned over, accompanied by a faint silver glow, and an extra object suddenly appeared in the palm, which was the Tiangang cold iron that he had obtained at the Broken Sky Auction.

Picking up the slightly heavy strange piece of iron, the kind of cold that penetrates his heart can't help but make him frown slightly, this baby is born with a sharp aura, which is already worth most of the divine weapons.

"Tianfeng, now!"

As soon as his mind moved, the Demon Flame Heavenly Phoenix slowly emerged from the air.

"What? are you going to finish this piece?"

As soon as he came out, Demon Flame Tianfeng caught a glimpse of the iron sword and Tiangang cold iron in his hand.

"Well, I still need your help. Gu Chen smiled, he knew very well that after his strength declined, his control of the reincarnation demon flame would not be as handy as before, so he had to let the demon flame Tianfeng assist from the side to ensure that nothing went wrong.

In fact, when he got the Tiangang Cold Iron, he had already made up his mind to use the Reincarnation Demon Flame to refine it, after all, for this extremely hard treasure, it was impossible for an ordinary flame to move it no matter what.

"Got it, you can do it. Demon Flame Tianfeng nodded, and then a demonic pink glint flashed in his eyes.

The next moment, I saw Gu Chen's eyes slightly downcast, and with a flick of his fingers, a subtle pink demon flame appeared on his index finger, the flame was slightly twisted, and at a glance, there seemed to be a noble phantom flying in the flame.

The left palm was lightly raised, and the Tiangang cold iron was in front of the demon flame, and then the index finger shook suddenly, and in an instant, the originally twisting and twisting flame actually burst out, only turning into a foot-long fire knife, and the blade was still burning with palpitating energy.

Whoosh!

The index finger slashed downward, and the fire knife slashed along the edge of Tiangang's cold iron.

Bite!

A small piece of Tiangang cold iron the size of a thumb fell off in response to the sound and fell straight into the palm of his hand.

Putting down most of the rest of the cold iron, Gu Chen pinched the part of Chelo with his fingers, the incision was neatly flattened, and the mirror surface was smooth, and because it was cut by the extreme flame power, there was still a trace of extreme heat left in the cut.

In his opinion, casting this sword only required so much Tiangang cold iron, and it would be a waste to have more, and he had never tried to use Xuanhuo to refine it, and even he didn't know what kind of situation he would encounter in the process.

If one accidentally fails to refine it, it will be a waste of this cold iron.

"Be careful, I'm going to start. He said softly, and then, I saw his left palm shake again, and with a buzzing sound, the demon puppet power instantly covered the palm.

As soon as his mind moved, under his control, the demon puppet force immediately held up a small piece of Tiangang cold iron and placed it in the air, and then the index finger lightly touched the air, and the reincarnation demon flame broke away in response to the sound and shot towards the Tiangang cold iron.

Zizi!

Curling white smoke slowly rose from the flames, and an unusually slight burning sound resounded in the air, and in front of him, the Tiangang cold iron placed in the reincarnation demon flame was constantly tumbling up and down, and as time passed, the layer of crystal iron on its surface was also melting extremely slowly.

It's just that the melting speed is a little slower.

"Hmmm, no, how could it be so slow. Gu Chen was puzzled, thinking that with the flame power of the reincarnation demon flame that burned the heavens and the earth, the speed of burning Tiangang's cold iron would be so slow now, which really made him a little puzzled.

Push it a little harder!

Thinking of this, the pink glint in the eyes of the Demon Flame Tianfeng beside him suddenly bloomed, and in an instant, a more staring flame spat out from its mouth, merging with the flames in the air, and continuing to burn.

When this second reincarnation demon flame was added, the melting speed immediately increased significantly, but the flame power was increased, but Gu Chen was in trouble for a while.

Due to the downgrading of his own strength, the flame that should have been controlled at his fingertips was a little incessant at this time, and several times during the period, he wanted to change the burning point, but he was tired and sweating, if it weren't for the Demon Flame Tianfeng from the side, this piece of Tiangang cold iron would have been wiped out long ago.

Zizi!

Droplets of metallic liquid gradually appeared in the flames, and every time a drop appeared, Gu Chen would immediately control the demon puppet power and wrap it all, otherwise in this kind of flame, this droplet would not last long.

One drop!

Two drops!

......

He was slightly relieved when a full ten droplets appeared, this number of Tiangang cold iron droplets was enough for the refining of this sword. All that needs to be done is to merge the droplets back into the iron sword, and you're done.

It's just that it wasn't until this moment that Gu Chen felt tricky.

For example, today's Gang cold iron has been melted by the reincarnation demon flame, but when it is integrated into the iron sword, it is not so easy, you know, although these droplets are wrapped by the demon puppet power, but the reincarnation demon flame is also burning under it all the time, if the flame is removed, these droplets will be instantly frozen when cold, and they will return to their original state.

And that iron sword can't withstand the scorching of the reincarnation demon flame, it is estimated that even if it is lightly touched by this flame, it will be enough to destroy it in one fell swoop.

"Damn, that's good. ”

Gu Chen's sword eyebrows frowned, and while controlling the reincarnation demon flame, he looked at the dark iron sword bitterly, not knowing what to do.