In Genshin Impact, The Final Chapter is the third and final quest in the Aginhotra Sutra World Quest series. It starts automatically when you complete both Starry Night Chapter and Risen Moon Chapter (in any order). The quest takes place in and around the Mawtiyima Forest in Sumeru, north of the Lokapala Statue of the Seven.
How to get the Yajna Grass
Follow the marker to meet Aranaga in Mawtiyima Forest. The Yajna Grass is almost directly above you, and there are no markers to show you the best route. If you’ve unlocked the Teleport Waypoint to the southwest of Mawtiyima Forest, then teleport there and glide down to your objective. Otherwise, you’ll have to clamber up the southern end of the valley where there’s a kind of bridge of plateaus leading to the objective.
Now that you’ve found the Yajna Grass, you have to unseal it, much like you unsealed the Barsam Flower during Risen Moon Chapter. Go to the southwest objective first. It’s easy to get to from the southwest Teleport Waypoint. Use the Kusava to raise the plant out of the pond, then use the bouncy mushroom to reach the plant and touch it. Next, glide east to the next plant. This time, once you’ve raised the platform with the Kusava, you’ll need to use the Four-Leaf Sigil to get to the plant and touch it. From here, glide north and return to the Yajna Grass, then use the Four-Leaf Sigils to cross to the final objective at the northern end of the valley. Summon Dendrograna using the Auspicious Branch, then use charged or aimed attacks on the three floating Dendro things surrounding the plant. This will remove the forcefield, allowing you to use the Four-Leaf Sigil to get to the plant and touch it. Now you can go back to the Yajna Grass and pick it.
How to clean up the Mawtiyima Withering Zones
Glide back down to Aranaga’s little garden, and talk to Aranaga. Open the Paimon menu, go to Time, and wait until midnight. Talk to Aranaga again, and again, then follow the marker to Jamikayomars. Next, follow the markers into Mawtiyima and glide over to the first polluted area on the right. For some reason, you may need to re-equip the Kusava at this point.
In this first area, you need to use the green Kusava power to destroy a stone, and the yellow one to repair a plant. Touch both plants, then summon Dendrograna and use a charged or aimed attack on the Withering Branch. Follow the Seelie to the next polluted area, using the Four-Leaf Sigils. Here you need to repair one plant using the yellow Kusava power and raise a platform using the red Kusava power. Then, once again, touch both plants, summon Dendrograna, and destroy the Withering Branch. Follow the Seelie to the third area, where you’ll need to use the green power and the red power. You’ll come under heavy Withering fire here, but there’s a Candle of Light near the Auspicious Branch if you need it.
Glide down to the marker and defeat the mutated fungi, then destroy the Tumor of Withering. To get back up to the Aranara, go up the slope to the northwest, then follow the chain of Four-Leaf Sigils. After this conversation, The Final Chapter, and the Aginhotra Sutra series will complete.