Yuyo

Yuyo is an aura you can only study from screenshots. It is flagged as a developer-exclusive that cannot be rolled, with no creator listed and no release version, and the Sol's RNG Wiki says it was added in Era 8 and has apparently been used only twice, which is why the page has little more than two images to go on. Its listed rarity is a joke written in Korean: one in a word meaning dog bamboo, a meme name that appears on the decal.

What the wiki does describe is a striking trick. Like the aura Impeached : i'm peach, every effect comes from one image, here two dogs cuddling with a snowy mountain behind them. Copies of that image shoot out from below the player and from the torso, and they trail around the head like a halo, much like the orbs on Impeached. People who saw it in use call it one of the most effect-heavy auras in the game. The font is Fuzzy Bubbles.

Because it cannot be rolled, none of the usual luck math applies and no biome helps.