Eywa's Roots are strange, spiral shaped plants that grow on the Pandoran surface. Na'vi can connect their queues to it. They often walk away with omens and warnings.
Avatar: The Game
In the NDS Game, Nok connected to several of these and was able to explain the situation to Eywa. Understanding him, Eywa assisted Nok by opening a vegetal chest and granting him the weapons of a long dead hero.
Source
- James Cameron's Avatar: The Game (Nintendo DS) - Ingame Pandorapedia