Extraterrestrial Meteorite Iron Crystal was an immortal-artifact-grade material. Jiang Hao summoned the Universe Sword Casket and stored the Extraterrestrial Meteorite Iron Crystal in its materials section, intending to use it to upgrade his three treasured swords: Chunjun, Sword Wings, and Zhanlu.
Come to think of it, this function of the Universe Sword Casket was a minor bug. The system would not allow Jiang Hao to take items from mission worlds with him, yet he could carry swords and materials stored inside the casket.
However, the Universe Sword Casket's material storage was limited. At most, it could hold only a few cubic meters of items.
Next, Jiang Hao planned to forge flying swords and magical artifacts. This time, he intended to borrow the power of earthfire. First, it could improve the quality of the artifacts. Second, it would save him a great deal of spiritual power. After all, he wanted to forge many artifacts this time.
As for borrowing earthfire, Jiang Hao planned to find an active volcano.
The nearest active volcano was Mount Ben on Sild Island, Australia's only active volcano. Mount Ben was also Australia's highest peak, rising above snow and glaciers at an elevation of 2,745 meters.
Jiang Hao flew to Mount Ben on Sild Island. The surrounding coastline was steep and the terrain perilous. No humans lived on the island, and steam could still be seen rising from the mountain, proving that the volcano was highly active.
Jiang Hao cast a Fire Evasion Art on himself, then used the Earth Evasion Technique to burrow into the volcano. The volcano's interior was not entirely filled with magma; there were many hollow spaces. Near the main crater, Jiang Hao found a suitable platform.
Even though it was still a hundred meters from the magma, the temperature here was already