The post-game of Pokemon Brilliant Diamond and Shining Pearl introduces trainers to a ton of extra content.
In the main story, trainers are limited to catching Pokemon from the Sinnoh Dex and battling the Gyms throughout the region. Once a trainer has defeated Cynthia and become Champion, though, new doors open.
There are certain Pokemon only available in the post-game of Brilliant Diamond and Shining Pearl. Access to them is given once a trainer enters the Hall of Fame and acquires the National Pokedex after seeing every creature in the Sinnoh Dex.
Note: This article is subjective and reflects the opinion of the writer. It does not include any Legendary or Mythical Pokemon.
5 best post-game Pokemon in Brilliant Diamond and Shining Pearl
After obtaining the National Pokedex in Brilliant Diamond and Shining Pearl, Rotom can be found in the Old Chateau. At night, interact with the television on the upper floor of the building. This will start a battle with Rotom. Catch it and you'll have the Plasma Pokemon who can shift to various forms.
Shelgon's final form is Salamence. The powerful Dragon-type Pokemon is one any trainer will want on their team or just in their collection. Trainers have a chance at encountering one in the Rocky Cave and Dazzling Cave biomes of the Grand Underground in Shining Pearl after obtaining the National Pokedex.
Charmander, of course, evolves into Charmeleon and then into Charizard. Charizard is one of the most popular Pokemon of all-time and needs to be caught as soon as you get the National Dex. Look for the Kanto Fire-type starter in the Volcanic Cave, Sandsear Cave, and Typhlo Cavern biomes of the Grand Underground.
Larvitar will eventually become the almighty Tyranitar. Tyranitar is a staple of competitive Pokemon battling, so you need add it to your collection and train it as soon as you've beaten the main portion of Brilliant Diamond. As a BD exclusive, it can be found in the Spacious Cave and Big Bluff Cavern biomes.
Eevee has so many possibilities. It can evolve into several different Pokemon with different types, stats, and appearances. It can be bred with a Ditto to ensure plenty of Eevee are available to add all of its evolutions to the Pokedex. Just get the National Dex and look for it to have its own day in the Trophy Garden or get an Eevee Egg from Bebe in Hearthome City.