One of the easier ways to fill up the Pokedex in any of the main Pokemon games was by breeding Pokemon and hatching eggs. As expected, this mechanic makes a return in Brilliant Diamond and Shining Pearl. This requires trainers to bring one female and one male of a compatible Pokemon species to the Pokemon Daycare. For those looking to hatch Pokemon available via breeding, they may need the help of Ditto.
Since Generation 2, players have stuck Ditto in the Daycare with a Pokemon of the species
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