The DexNav is a brand new feature that appears on first sights to be a derivation of both the PokéRadar and the shaking spots that exist in Pokémon X & Y. Using this feature of the PokéNav Plus, you have the ability to hunt for various Pokémon.
As you are in the various routes, caves or in the water, there will occassionally be a Pokémon appear from the grass or water. You will see a shadowed form of the Pokémon, with some Pokémon like Poochyena, Skitty, Pikachu and Zigzagoon having special imagery, appear. From there, you need to sneak up on the Pokémon to begin a wild encounter with that Pokémon. If you move too fast, use the D-Pad, or are on a Bike, you will scare the Pokémon away. In caves and water, the Pokémon will often move causing you to change your strategy. You can't sneak when you have the Dowsing Machine equipped
When this occurs, the Dex Nav will activate and when activated, it will show you the Pokémon that you are finding, and more. In addition to this, if you approach a Pokémon in the overworld, you'll have the ability to scan them using the DexNav, which adds them to your Pokédex.
|DexNav - Interface|
When you are in each area, if you have the DexNav open on the bottom screen, you will see a small screen with the layout of the area done in the GBA style. Overlayed on this will be a variety of Pokémon. As you see more Pokémon, this will increase. Pokémon you have only seen and not caught will appear as transparent silhouettes. This showcases all Pokémon that are in the grass, ground, found while surfing or fishing
When you capture Pokémon, however, they appear fully on this. If you tap them on the interface, you have the ability to check their Pokédex entry, or to search for them. If you search for them and it finds them, then they will appear in a spot. To top that off, if you're hunting for a Pokémon normally found by fishing, it will appear in the water among the possible Surf Pokémon, which is very handy.
As you collect Pokémon, you may notice a crown of Bronze, Silver,Gold and Platinum. These crowns are used to indicate if you have obtained all of the Pokémon through each of the methods: Walking, Surfing, Fishing and DexNav exclusive. The more you capture, the better the crown.
|DexNav - Levels & Features|
The DexNav for each Pokémon is a unique thing. In these games, the Pokédex tracks the amount of times you have encountered the specific Pokémon. For each time you encounter them, either in the wild, in the overworld, or owned by a trainer in the game, then the level increases and is also viewable in the Pokédex under "Times Encountered". As the level increases, then the chances of additional features increases
When the Pokémon's entry in the DexNav is of a higher level, then you will see more of the Pokémon as you approach it. We'll get specific values as soon as possible
|DexNav - Chaining|
A lesser known feature of the DexNav is the ability to chain. When you get a hit and encounter a Pokémon, if you capture or defeat it, then immediately afterwards you will be able to search for it again and you are almost guaranteed to find one. If you do this repeatedly, then the chances of getting hold items, hidden abilities, egg moves and higher IVs is increased. The specifics on how much these are increased by is being calculated.
After you have encountered it 5 times, then the base level increases by 1 so Pokémon that would appear at Level 35 now appear at Level 36. This happens every 5 Pokémon in your chain. This continues on until they're up to 20 levels higher than normal, 30 levels if it gets the Level boost, and then will reset to normal. As your chain increases, the Pokémon will disappear quicker, or in the case of caves and in water, they will move spot very quickly causing you to have to sneak up on them faster and thus increasing the chance of your chain breaking. If you have a different wild encounter during the chain, then it will break. If you run from the Pokémon, then the chain will break..
|DexNav - National Pokédex|
After you have done the story with Primal Groudon & Primal Kyogre, you can go to Professor Birch and receive the National Pokédex. When you receive it, Professor Birch will inform you that the shift in the climate encouraged a variety of new Pokémon to appear within the region. In various routes, you will now discover non-Hoenn Pokédex Pokémon in the grasses and waters across Hoenn. Most areas now have three of these Pokémon and they can only be obtained by the special spots that activate DexNav. These can actually be found before getting the National Pokédex but after the story with Primal Groudon/Kyogre