Genshin Impact - Collei's Ascension Materials Farming Guide

gamespot.com:

Collei has just joined Genshin Impact's roster in version 3.0 as one of only two playable Dendro characters, alongside Tighnari. She's a four-star bow user who can be obtained for free at the moment, so there's nothing preventing you from adding her to your party right now. Collei is currently a must-have character simply because of how Sumeru is built--there are Dendro-related puzzles and mechanics all over the place. But if you're looking to level her up for real, here's what you'll need.

Nearly all of Collei's ascension materials can be found inside Sumeru, so most items should be relatively close to one another. Nagadus Emerald is an elemental stone that can be obtained by farming the new Jadeplume Terrorshroom normal boss. This green bird-like creature is located in the northwest corner of Sumeru. Alternatively, players can also convert other elemental stones into Nagadus Emerald pieces at any alchemy station.

Rukkhashava Mushrooms are mostly found in Mawtiyima Forest, Ashava, and the Ardravi Valley on the northern, western, and eastern sides of Sumeru. They're usually found on trees inside the rainforests. Here's a screenshot of where to find them, taken from HoYoLAB's interactive map:

Arrowheads drop from Hilichurl archers, and as you may already know, those enemies can be found in every single major region of the game. They're found all over Mondstadt, Liyue, Inazuma, and Sumeru, so farming for these drops should be easy. Check the Adventurer's Handbook in the menu for exact locations. Arrowheads can also be bought from the in-game shop using Stardust.

Majestic Hooked Beaks are brand-new items introduced in Genshin Impact version 3.0. The item only drops from the Jadeplume Terrorshroom normal boss, meaning that