White Knight's Icy Return Full Walkthrough and Details | Monster Hunter Stories 3 ( MHS3 )

The scrivener hopes that the player can raise the Barioth's ecosystem rank for research purposes.

Available after the the Main Story Reunion.

[1] Talk to the Courageous Scrivener at Serathis.

They're doing research on the Barioth but it's difficult since they have a small population. They want it to have an S rank Ecosystem so that there would be a bigger sample size to study.

[2] Raise the Barioth's Ecosystem Rank to S.
・First, make the Invasive Khezu retreat. It only comes out at night
・Next, enter the den of the endangered Barioth and acquire its egg.
・Restore the Barioth to any habitat
・Keep collecting Barioth eggs in the area and releasing it in its habitat to get an ecosystem rank of S

[3] Report back to the Courageous Scrivener.

・Ice Def Boost (S)
・Catalyst Key
・EXP x 25000
・Silver Trade Points x 1800