She's an inventor with an affinity for Legos. She also recently learned that she is an Inhuman with the uncontrolled ability to mind-swap with Devil Dinosaur.
Not cool for her, but it's fun to read about each month!
Anyway, I know that she's the smartest person in the Marvel Universe because Amadeus Cho (AKA the Totally Awesome Hulk and the sixth-smartest person in the Marvel Universe) said that she's the smartest in MG&DD #13. And because she did something with this device:
I'm not sure what the device actually is. That's probably because I'm not the smartest person in the world. I'm closer to being the 34th-smartest person in the world. But I do know that the device is a test of some sort. See?
A few boops later and Lunella managed to make the green lights change shape.
It takes a very special person to boop-boop the lights into the correct configeration. And that's how I know that Lunella Lafayette is the smartest person in the Marvel Universe!
(Presumably we readers will gain better insight into the nature of her genius.)
"Cosmic Cuties Part Six of Six: Unrequited" features words by Brandon Montclare & Amy Reeder, art by Natacha Bustos, colors by Tamra Bonvillain, and letters by VC's Travis Lanham.