Lyney ascension requires the "Emperor's Sentence" material, which can be obtained from the world boss "Emperor of Fire and Iron". To aid in your search for this boss, and to prevent unnecessary wandering, we recommend referring to the guide below on finding the "Emperor of Fire and Iron" boss location in Genshin Impact.

Ascension Materials for Lyney

Shortest Route to "Emperor of Fire and Iron" boss in Genshin Impact

Initially, our route to the location of the "Emperor of Fire and Iron" boss starts from the surface teleport point. If you haven't unlocked this teleport point, you can walk or swim to the indicated location via the nearby waterway.

Move directly forward relative to the character in the second screenshot above.

Next, you need to dive underwater.

If you've done everything correctly, you'll notice a sizable hole right beneath you - the entrance to a cave system. It may seem like there's no way in, but the entrance is hidden in the unremarkable textures of the rocks on the side.

Congratulations, adventurers! You've arrived. Here's the arena of the "Emperor of Fire and Iron" boss!