Xuan Yuan hurriedly asked, "Then what happened later?" Lianchenglong wanted to speak, and there was a roar from underground. Xuan Yuan looked down, and the light was getting brighter and brighter. Then the metal gate opened, and Lianchenglong quickly got inside.

Xuan Yuan hurriedly followed and entered the underground space. The metal gate closed quickly, and the flow of water outside stopped. The water temperature was very high, and Xuan Yuan hurriedly surfaced and jumped into a huge space! Xuan Yuan looked around and found that there was a large fireball in the sky, similar to the current sun. The trees here are unusually tall, growing to a height of a kilometer.

Xuan Yuan rose into the air and looked into the distance, the space here was not large, only half the area of the Beixing Mountain. The roar of the Liancheng Dragon was heard in the distance, and Xuan Yuan hurriedly followed.

Xuan Yuan came to the middle area of the space and saw more than a dozen giant houses. In the distance, the dragon fell to the ground and communicated with a red giant. The red giant saw Xuan Yuan and waved his huge palm. The 500-meter-tall giant spoke: "Welcome to the Blue Star people." You are very trustworthy, tens of thousands of years have passed, and it has not disturbed our lives. ”

Xuan Yuan was stunned in place, not knowing what was going on! The giant opened his mouth and said, "We have a symbiotic relationship with the Blue Star people. The planet is young and inhabitable underground. So we live underground and provide technology to the Blue Star people on the ground, and the Blue Star people are responsible for keeping secrets. It was 30,000 years ago that the previous generation of inheritors arrived. We helped the Blue Star people and drove out the alien rule. In return, all their high-ranking personnel retired and lived in the deep mountains and dense forests, keeping underground secrets for us. ”

Xuan Yuan reacted and said, "I understand." The sacrificial clan of Nanshanzhai is actually the founder of the Blue Alliance. But all of them are hidden from the world, guarding your secrets. ”

The giant praised and said, "You are also good, you have a fifth-order energy source. It's a pity that our inheritors can only inherit the source of the soul. ”

Xuan Yuan asked puzzledly: "Ask what must be made the source of the soul?" The giant spoke, "Because only the source of the soul can erase the deepest memories and make the creatures on the ground know us!" There is no need to erase your memories until the war is over. Okay, you can go back first. ”

Xuan Yuan was even more puzzled and asked, "You don't go to the ground to help?" ”

The giant did not answer, he roared, and more than a dozen giants of 300-400 meters appeared. More than a dozen giants gathered together and slowly moved a mountain.

Lianchenglong opened his mouth and said, "I'm going to the underground civilization now, it's a world of high temperatures, and it's hard for terrestrial creatures to withstand it. Luckily, now I'm a mechanical creature and I'm not afraid of the heat. ”

Xuanyuan hurriedly said, "How long are you going?" Lian Chenglong thought for a while and said, "The giants say that W Star is difficult to deal with. They have to help me become a fifth-order powerhouse before I can return to the ground. It is not easy to break through the fifth order, and the time should be three or four months. ”

Xuan Yuan nodded and said, "Okay, I'll look at the Azure Base Group." You have to bring a message to the brothers, otherwise Jade will make trouble for them! ”

Lian Chenglong nodded and left a message into the communicator. Lian Chenglong continued to explain: "It's a million-year-old secret, don't tell anyone else yet, just know about it." By the time I show up with the Underground Giant, W Star will definitely have suffered a lot of losses. ”

Xuan Yuan nodded and said, "I understand this." After saying that, Xuan Yuan sent out an energy enchantment to protect the Liancheng Dragon.

Xuan Yuan turned around and said, "I'm leaving, you are the most potential teenager, you will definitely be able to break through the fifth order." ”

Xuan Yuan rose into the air and rushed towards the entrance. Lianchenglong opened the gate, and Xuanyuan returned to the surface through the river.

The dragon closed the entrance, and the giant had moved away from the hill. Below the hill is an underground passage, and going down here is the real underground world.