Another New Skill for Dawn Warriors

...What is it? A new skill? ...It must be 나인하트 again. I already know how stubborn you are with this, so I will teach you the skill, with one caveat of course.

Head over to the 4th Drill Hall of 연무장 입구, and take the test. After that, bring back 능력의 증표, and I will teach you the new skill as promised.

You once had a stubborn will to succeed... Where did it go? I miss that about you.

I am impressed to see that you have brought back 능력의 증표. You are definitely ready to learn this skill.

I will now teach you a new skill for the Dawn Warriors, Advanced Combo Attack. Use this skill to bring honor to the Empress.

You have yet to bring back 능력의 증표, which is understandable. The test is set up at the 4th Drill Hall of 연무장 입구. It's a similar spot, but the difficulty has been raised quite significantly.