The DexNav's main function is to give information about the wild Pokémon in the area, but this information can be viewed and used in different ways. You can use the DexNav to its fullest potential in a variety of ways, but I think Shiny Hunting is the most prevalent, explained in the following list. Here are the DexNav's main functions:
- Catching Progress: Shows the caught Pokémon on the map, and shows a silhouette of the encountered but not caught Pokémon.
- Found Pokémon Count: Shows the amount of times a certain Pokémon has been encountered.
- Search Function: Lets you manually search for a previously caught Pokémon. This will switch you into Hidden Pokémon:
- Hidden Pokémon: Similar to normal hunting, a previously unseen Pokémon will be able to have specific info shown and hunted through sneaking if you click on the magnifying glass circled with red.
- Detector Mode: Identifies non-hidden overworld Pokémon and registers them as encountered. These Pokémon can be found in cutscenes or normally roaming, and they cannot be normally encountered.
- Search Level: Displays the amount of times a certain Pokémon has been encountered.
- Shiny Hunting: Search Level and other variables influence Shiny Hunting, which is primarily used through the DexNav. More info about shiny hunting here.
- Chaining:
A chain builds every time the player captures or defeats a hidden Pokémon of any species. If the player does not capture or defeat the Pokémon (whether the player chooses or is forced to flee, such as by Roar, or the Pokémon escapes, such as by Teleport), the chain breaks. A chain will also break if, outside of battle, a hidden Pokémon appeared and is not encountered (whether by scaring it away, waiting too long, walking too far away, leaving the area, or entering a different battle). The chained Pokémon do not need to be found using the Search function, and the message "The Pokémon couldn't be found. Try looking in a different area!" does not break the chain if received when the Search function is used.
Hope I helped!
DexNav Bulbapedia Page
