Unlimited super rare metal BUG:

First of all, you need to arrive at the ワナナバニ Research Institute and complete the mission "キーマンをExploration". After completing it, go to B2F, which has been opened but is closed. Use "Research Institute's のカギ" in front of the status door, so you can complete this task again. In addition to 2000 experience points, the reward for completing the task is a super rare metal. Therefore, you can get unlimited super rare metals.

PS: I have not tried it because there is this BUS. In order to save time, I used Jinshan to adjust it.

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