In all Mainstream Pokemon Games, there are certain techniques players can use to increase the spawns of Wild Pokemon. In Pokemon Sword & Shield, this is no different. In fact, there are actually three known ways to manipulate certain Wild Pokemon appearing. The first, and most obvious, thing one can do to increase the spawns of certain Pokemon is simply by defeating that same Pokemon over and over again. Of course, the only way to properly do this is with Pokemon that appear in the Overworld.
The second method one can use is by going into their Pokedex and seeing the Recommended Pokemon for a given area. As long as a Pokemon is listed as Recommended, it will have an increase in spawns for that given location. This list will even update should you catch all the Recommended Pokemon of an area or naturally from day to day. And finally, having Pokemon in your party with certain Abilities will cause increase spawns with specific types of Pokemon: Flash Fire will cause an increase in Fire Type Spawns, Harvest will cause an increase in Grass Type Spawns, Lightning Rod will cause an increase in Electric Type Spawns, and Storm Drain will cause an increase in Water Type Spawns.
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