Brilliant Pokémon

As you play through the game, you will sometimes see Pokémon surrounded by a "brilliant aura". This golden coloured aura signifies that it has a special boost over certain Pokémon. Each Brilliant Pokémon will force the level of the Pokémon you encounter to be the highest in its wild encounter slot

The ability to find a Pokémon with a Brilliant Aura is completely random, but does increase as you capture more Pokémon. The more Pokémon you catch, the more likely you are to find one. When you catch one, you'll also end up collecting Watts, the currency used in the Wild Area. The rates go up and never go down. You'll never find a Pokémon with a Brilliant Aura until you have caught or battled at least one of the species

The chances of getting a Shiny Pokémon are increased with Brilliant Pokémon.

There is another way to get Pokémon with the Brilliant Aura: Chain Fishing. In previous games, Chain Fishing was used in order to get Shiny Pokémon but in Pokémon Sword & Shield it works to get Brilliant Pokémon. Here, if you fish multiple Pokémon consecutively without failing to get the hook, catching, running away or leaving the area, you have a higher chance of finding a Brilliant Pokémon. However, if you fail to get the hook, catch a Pokémon, run away or leave the area, your combo is broken and the rates reset

Pokémon with Brilliant Aura are special in multiple ways. First off, they have at least two guaranteed IVs at maximum. In addition to that, they will also have an Egg Move that the species can usually get only by breeding. For example, if you caught a Rookiedee in Route 2, it could end up having the Egg Move Sky Attack.