The Trash-Eating Phoenix King

Aiden Scott transmigrates into a book, arriving in the Clearwater Continent as an egg of the Mystic Bird family. Hatched, he's seen as a low-level mongrel duck due to grey feathers. He awakens a system to level up by picking up trash. Collecting trash, he grows stronger, awakens his Phoenix Bloodline. He defeats foreign tribes with Nirvana's True Flame, becoming the savior of his family. He eventually becomes the new lord of the Clearwater Continent.