Lee Joon-gi has declared to become Inaisin-gi, as per Ara Moon’s final will in Arthdal Chronicles: The Sword of Aramun

In the 5th episode of the tvN weekend drama ‘Arthdal Chronicles: The Sword of Aramun’ that aired on September 23rd (written by Kim Young-hyun and Park Sang-yeon, directed by Kim Kwang-shik), Tan-ya (played by Shin Se-kyung) found Ara Moon Hae-sla’s last will.

Tagon (played by Jang Dong-gun) and Tae-alha (played by Kim Ok-bin) faced a crisis while trying to save their son, Aroq (played by Shin Se-woo). Tagon’s blue blood was revealed, exposing his identity as Igut. Tan-ya, through the swapped identities of Saya (played by Lee Joon-gi) and Eun-seom (played by Lee Joon-gi), learned of Tagon’s identity as Igut and, in line with Ara Moon’s white mountain prophecy that recognizes Tagon as Igut, saved Tagon.

People painted the Ara Moon statue in purple and, while they accepted Tan-ya’s words, they also expressed confusion. Tagon collapsed and, upon waking up, was tormented by the auditory hallucination of his father’s words, “Kill everyone who has seen your blood.” Tan-ya found Ara Moon’s last will and testament, which was also his final trust: “When the oak tree splits and reveals my sword, Ara Moon will deliver the mission.”

Tan-ya explained that, since Eun-seom is Igut, recognizing Tagon’s identity as Igut was necessary, as it would lead to Ara Moon coming to life and saving Arthdal. However, Eun-seom believed that, as Inaisin-gi, he couldn’t become Ara Moon. Eun-seom bid farewell to Tan-ya with tears and promised, “I’ll definitely come back.” However, as he tried to leave Wahran again, he was stung and kidnapped by Tae-alha.

Meanwhile, Saya met Chae-eun (played by Ha Seung-ri) and received the Ekomahis stone. The stone belonged to Eun-seom and Saya’s father, Raghaz, who separated centuries ago with the intention to reunite someday and recognize each other. Saya, thinking that Eun-seom had taken his place in Arthdal and become Tan-ya’s lover, was disheartened.

Tae-alha kidnapped Eun-seom and questioned his true identity. Nunbyeol (played by Lee Si-woo) witnessed Eun-seom’s abduction and informed Tan-ya, who, along with the people of Wahran, rescued Eun-seom. Yul-saeng (played by Jung Seok-yong) warned Eun-seom, showing him an iron sword, “Arthdal has come this far. Go there, show it to Wahran, and persuade them to save those who will die in vain.” Eun-seom planned to return to Wahran but was stopped by Yang-cha (played by Ki Do-hoon).

Yang-cha believed that Eun-seom would endanger Tan-ya, so he tried to kill him. Eun-seom fought with Yang-cha, and during the battle, he was struck by a thunderbolt, which left a lightning scar on his arm. As the oak tree mentioned by Tan-ya split and revealed Ara Moon’s sword, Eun-seom declared to Yang-cha, “Tell the Great Priest: I will become both Inaisin-gi and Ara Moon Hae-sla. When Ara Moon’s sword is found inside the oak tree, I will deliver the mission from within the oak tree.”

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