In Route 212, there is a Mansion where a few people live. Out back there is a patch of grass which is predominantly inhabited by Roselia, Mukubird, Pichu, Pikachu and Kricketune. However if you talk to the owner in the room to the right, you can activate something else.

Every day if you talk to him, he'll walk out. Go back in and he'll be there and tell you of a Pokémon that is inhabiting the place today. Sometimes its a Rare Sinnoh Dex Pokémon, others its a Non-Sinnoh Dex Pokémon so be alert. They are however there all day so you can go back. Their level averages at Lv. 16 to Lv. 19 so bring a Pokémon of that level. You have up to two of these Pokémon at once, they have a low encounter rate in the Mansion and the two Pokémon are the one allocated Today and Yesterday

Below are all the Mansion Pokémon and the routes/areas they swarm in:

Mansion Pokémon

Nat No. Pic Name Type 1 Type 2
#035 Clefairy  
#039 Jigglypuff  
#052 Meowth  
#113 Chansey  
#133 Eevee  
#137 Porygon  
#173 Cleffa  
#174 Igglypuff  
#183 Marill  
#298 Azurill  
#311 Plusle  
#312 Minun  
#351 Castform  
#438 Bonsly  
#439 Mime Jr.  
#440 Happiny  

 
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