The Mu Zi Chronicles

The only blade of grass in the world capable of cultivating immortality practices the world's most useless technique. The weakest creature and the most useless cultivation method make a feeble combination, and unlike other protagonists, it doesn't get an easy ride. Instead, it dies several times and gradually learns how to survive by keeping a low profile. It cultivates both the Dao and the heart, until it becomes a supreme being. As it turns out, even grass can cultivate immortality!