Catching all the Pokémon in the Galar region takes time, but it narrows down the list and pinpoints some of the more difficult to find Pokémon Sword and Shield. There is a decent Pokémon called Ferroseed that you catch in multiple locations. It's like a Grass and Ice Pokémon that you can involve in a Ferrothorn at level 40.
You can find Ferroseed in these places:
- Motostoke Riverbank during a sandstorm
- Stony desert during a snow storm
- Bridge Bridge during Normal, Cloudy, Rain, Thunderstorm, Intense Sun, Snow and Hail, Snowstorm, Sandstorm and Heavy Fog
- Route 4 in all weather conditions
You want to check out Motostoke Riverbank during a sandstorm to have the best chance of catching this elusive Pokémon. You must use a Fighting or Fire-type Pokémon to do a fair amount of damage against it. Most of the Ferroseed Pokémon you will encounter will range from level 26 to 28, but if you find one on Route 4, it is much lower, between levels 13-15.
You have the opportunity to meet him in a Max Raid in the wilderness, but there is little chance of that happening. You'd better check the other three locations during those particular weather periods to get the best chance of catching an ideal Ferroseed. If you encounter him in a maximum level raid, his level ranges from 25 to 30.
Keeping this Pokémon on your list is ideal, especially if you get it early on Route 4. You can choose to evolve it at level 40 into a Ferrothorn, and it remains a Grass and Ice-type Pokémon. You won't need anything special to change it.