After the recipe encyclopedia and the list of medicines, the system finally extended its claws to the field of mathematics.

The sword array is composed of four evenly matched famous weapons, so it is named the square sword array, and the logic is rigorous and there is nothing wrong.

"Isn't our name a bit sloppy, though?" Chen Nan asked after discussion.

"It represents the righteousness of Haoran, and the sword qi comes out to suppress the demons; The square represents the round sky and the place, and the four divine swords guard the four directions; The shape represents the intangibility of the elephant, and the realm of the sword is one, which can kill the enemy invisibly. The system said, "Every word has a deep meaning, why do you think it's sloppy?" ”

I don't read much in the system, don't lie to me.

When did the square have so many explanations, the math teacher's coffin board couldn't hold it down.

"Host, you haven't gone to school after all, I can understand it," the system conjured a big hand in Chen Nan's sea of knowledge, and patted Chen Nan's spiritual projection, "If you don't have culture, you have to study more, and this system can also be exchanged for five years of college entrance examination and three years of simulation." ”

"I just haven't been to school, it's not that I haven't been to school, pay attention to your wording." Chen Nan was a little speechless.

Before I met the system, I was a rich second-generation person, although I didn't go to school because of physical reasons, but the private group I invited went straight from elementary school to university.

"These are not the point, the square sword formation is still far away from you, and your top priority is to exchange for the Seven Star Dragon Yuan." The system says, "Just make your choice." ”

Chen Nan looked at the [Redeem Now] and [Redeem Now] in front of him, and reluctantly chose the former.

【Ding! 】

[Congratulations to the host for completing the following redemptions]

【Perfect Body Sculpting Capsule x2 Total 2000 Points】

【Star Core Expansion Impact x2 Total 2000 Points】

【Ten Perfect Tonic Pills x1 Total 1000 Points】

【Toei x1 Total 1000 points】

【Famous Weapon: Seven Star Dragon Abyss (Inverted Mold) x1 A total of 80,000 points (you can enjoy a half-price discount, 40,000 points will be deducted)】

【Famous Weapon: Seven Star Dragon Yuan (Reverse Mold) x1 A total of 8000 points (you can enjoy a half-price discount, 4000 points will be deducted)】

"Host, you earned 44,000 points for nothing this time, how can you thank me?" The system says.

Listen to what people say?

No, the system is not a human after all.

Thinking about it like this, Chen Nan felt that his heart was much smoother.

"I thank you."

Chen Nan urged the star core to prepare to try the seven-star dragon yuan sword he had just gotten.

Eight Thousand Runes belong to the category of B-level mysteries, and can only be mastered after reaching level 11. Chen Nan's evolution reward is still in progress, and he is currently at the peak of level 10, and if he doesn't use multiple mysteries at the same time, he can barely summon them to try his hand.

A touch of purple gas appeared in the room, and with it, the sky was full of stars.

The five-foot Qingfeng appeared in Chen Nan's hand, and the chilling aura broke through the sword body, permeating every corner.

Chen Nan looked at the famous weapon in his hand, and dared to name it after the mythical and legendary divine weapon, this weapon is definitely very mysterious.

At the hilt of the sword are seven stars arranged into a dipper, the purple sword body is like a giant dragon breaking into the sky, and it seems to fly out of the abyss, the dragon body is a sword edge, the dragon head is a sword, and the stars are always filled around.

Legend has it that in order to forge this sword, Ou Yezi chiseled up the mountain, introduced the stream water in the mountain into the pond arranged according to the Big Dipper, and built a unique sword-casting furnace, using the combined force of Tie Ying, cold spring and bright stone to cast this sword, named Longyuan.

This instrument is a true reproduction of the legend.

Holding the famous sword that seemed to have crossed over from mythology, Chen Nan felt the raging sword intent in his body.

Purple qi surrounded his body, and with each rotation of Zhou Tian, Chen Nan's understanding of sword intent deepened.

The Seven Star Dragon Yuan seemed to be a key, opening the sword intent that Chun Jun and Chi Xiao had left in Chen Nan's body two days ago, and the three sword intents were intertwined in his body, gradually fusing with Zhihai.

According to this trend, Chen Nan could build a bridge between the star core and the sea of knowledge in two days, and let the sword intent go up the bridge to break through the shackles of the thirteenth level.

"Good sword!" Chen Nan sighed.

Expensive things have no other disadvantages besides being expensive, and there is some truth in this sentence.

Chen Nan's original painful emotions were swept away.

With a slight swing of his sword, Seven Star Long Yuan slashed out a light purple wind blade and rushed away from the surrounding stars.

This is the characteristic of the "wind" that comes with the Seven Star Dragon Yuan, and this characteristic is only attached to famous weapons.

The mystery itself does not have attributes, because its rune arrangement is the same, and the evolutionaries of the four attributes of earth, water, fire, and wind can all use the same meaning, and the blessings of different attributes will make the mystery take on different forms.

However, the name weapon will have a certain characteristic, which is somewhat similar to the four attributes of earth, water, fire, and wind.

When an Evolver reaches the Advanced Realm, they can swim in the Elemental Ocean and come into contact with the four basic elements, thus creating a high-level mystery with different characteristics.

This kind of mystery can make up for the lack of attributes of the evolutionary to a certain extent, so that the evolutionary of a single attribute can feel the original characteristics of different attributes, and add inspiration for further improving the path of evolution.

Chen Nan took advantage of the famous inverted mold, and was also able to feel the four origins in advance, which laid a very solid foundation for the impact of level 13 in the future.

The wind blade is like a heavenly soldier cutting through the galaxy, forming ripples in the room.

"Even the sword momentum is so amazing, I really want to fight people for hundreds of rounds." Chen Nan looked at the Seven Star Dragon Yuan Sword with a look of intoxication.

【Ding! 】

[Detects the host's strong demand for coercion, triggers a random task]

[Mission Name: Fast and Furious (410)]

[Mission content: The host needs to defeat three Dongying Evolutionaries above level 10 with the Seven-Star Dragon Yuan Sword within two hours]

[Quest Reward: Get 2 random items]

[Failure Punishment: Host paralyzed lower body for 24 hours]

This system is really smart, and the host just drifts a little and sends the task in time.

Chen Nan took a serious look at the punishment of the task, and suddenly felt a little big.

"System, can I retract that sentence just now?"

……