South Korea, officially the Republic of Korea, is a country in eastern Asia.
U-GIN Genetic Research Facility
Ultron and the Maximoff twins later arrived in Seoul, South Korea where he arrived at the lab of U-GIN Genetic Research Facility and confronted the Avengers' ally Doctor Helen Cho. Ultron informed her that he intended to use the Cradle to create the perfect, synthetic, humanoid body for Ultron, made from Vibranium. When Cho resisted Ultron used the Scepter to take over control of her mind and force her to do his bidding.
As the synthetic body was built inside the Cradle, and was given a Vibranium composition on Ultron's request, thus making it more durable, Ultron revealed to the Maximoff twins the power contained inside the Scepter: an Infinity Stone, with which Ultron would integrate with his new synthetic body and adopt god-like powers. Cho then plugged Ultron into the machine to upload his base consciousness into the being. When Wanda Maximoff attempted to read Ultron's mind through the synthetic body, the being allowed her to discover that Ultron's actual plan was to cause a global catastrophe that would usher in a new age of Earth's evolution.
Ultron attempted to defend his actions, noting that there was no room for the weak in the world, however, doubting Ultron's cause, Wanda removed Ultron's mind-control over Helen Cho in secret to allow her to sabotage the upload. Ultron sensed that the Avengers had arrived in Seoul to stop his plans and ordered his soldiers to evacuate. However Cho used the opportunity to stop the upload, in response Ultron fired a blast of energy at her which stunned her, in the chaos the Maximoffs escaped and Ultron was left with no choice but to move the Cradle onto a truck and escape.
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