The quest includes three steps that should be fulfilled sequentially. When you start completing the first one - the other two are locked and each of them becomes available upon passing the previous one. As soon as Mammoth goes to the first expedition, you can proceed with the quest so it could adventure further.
The feature of the task is that commencing with it activates the timer for 24 hours. In case you don't pass to the second and the third stages during this time period, the quest performing should be started from the beginning.
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