This is a guide for ascending Ethel in Xenoblade Chronicles 3. How to make Ethel undergo the maturation process.
Among the Heroes, Ethel is quite the unique case. You’ll first recruit Ethel and acquire her class near the start of Chapter 2. However, moments later, Ethel will leave your party. She’ll then remain absent until near the end of Chapter 6.
Once you get Ethel back though, she cannot fight like how she used to. Although there is something you can do about it.
How to Undergo the Maturation Process
Like the other Ascension Quests, you must reach Rank 10 in Ethel’s Flash Fencer class (for somebody other than Ethel). In this case, it’ll be Noah.
Afterwards, if you check Ethel in the Hero Roster, it’ll outline the conditions for her Ascension Quest, but honestly, they shouldn’t have bothered because it tells you next to nothing.
That said, you might be able to figure it out with some lateral thinking.
Before that though, there are two more conditions. Cammuravi’s Seraph class must also be Rank 10; since Taion inherited the Seraph class, the task falls on him. Next, you must have Cammuravi in your battle party.
Once you’ve met those three conditions, return to Colony Omega, preferably by fast-traveling to the nearby camp. Then enter the lab. As you approach the lab, your party members will comment about revisiting the lab. Now approach the second door that’s normally locked; you should be able to enter, whereupon a cut-scene will play.
When prompted, agree to have Ethel undergo the maturation process. If you decline, simply inspect the cradle to receive the option again. Do so and Ethel will return to her old form. You can now add Ethel to your battle party again. Also you can now reach Rank 20 in the Flash Fencer and Seraph classes.