In the fourth generation of the Pokemon games, several new Pokemon evolutions previously added have been incorporated into the Diamond and Pearl franchises and the Sinnoh region. One of those Pokemon was Weavile, the evolved form of the Ice / Dark Pokemon from the Johto region, Sneasel. Weavile isn't too hard to get in Pokemon Brilliant Diamond and Shining Pearl, but you'll need to meet a few conditions first. So, let's get into the details of this evolution process.
To get Sneasel and Weavile in Pokemon Brilliant Diamond and Shining Pearl, you will obviously need a Sneasel first. Sneasel shouldn't be too hard to find, as Johto-era Pokemon can be found on the snowy paths leading to Snowpoint City.
From here, you'll need to do two things: wait until sunset and have a Razor Claw. Sneasel must hold the Razor Claw in his hand and in order for the Ice / Dark Pokemon to evolve into Weavile, he must level up overnight. An easy way to level up Sneasel is to fight the weakest Pokemon in nature, especially those that are weak to your Sneasel's moves, or by simply giving him a rare candy.
Do that and you will be able to get this Gen 4 Pokemon in no time.
