Upper Steelmouth Plant has 2 different map pools total. If you are unsure whether you are in the correct location within the building, a good way to check is to compare common Pokémon you encounter with the guide below, as each area is unique.
| Floor Encounters / Main Entrance | ||||
|---|---|---|---|---|
| Common | ||||
 #019 Rattata |
 #041 Zubat |
 #074A Geodude (Alolan) |
 #109 Koffing |
 #309 Electrike |
 #316 Gulpin |
 #412St Burmy (Steel) |
 #436 Bronzor |
 #595 Joltik |
 #777 Togedemaru |
| Rare | Legendary | Ultra Beast | ||
 #110 Weezing |
 #137 Porygon |
 #778 Mimikyu |
||
| Floor Encounters / Downstairs | ||||
|---|---|---|---|---|
| Common | ||||
#019 Rattata |
#041 Zubat |
 #081 Magnemite |
 #088 Grimer |
 #088A Grimer (Alolan) |
 #100 Voltorb |
 #374 Beldum |
 #568 Trubbish |
 #599 Klink |
 #848 Toxel |
| Rare | Legendary | Ultra Beast | ||
 #089 Muk |
 #101 Electrode |
#137 Porygon |
 #145 Zapdos |
 #796 Xurkitree |
Other locations
| Routes |
|---|
| Route 1 · Route 2 · Route 3 · Route 4 · Route 6 · Route 7 · Route 8 · Route 9 · Route 10 · Route 11 · Route 12 · Route 13 · Route 14 · Route 15 · Route 16 · Route 17 · Route 18 · Route 19 · Route 20 · Route 21 · Route 22 · Route 23 · Route 24 · Route 25 |
| Caves/Indoor Areas |
| Craggy Stairway · Crysterra Hollow · Fungal Cavern · Nightshade Crypt · Scorched Sanctum · Unown Cave · Upper Steelmouth Plant · Wellspring Pass |
| Towns/Outdoor Areas |
| Mudbray Ranch · New Haven · Nightshade · Shore's End · Starfall · Stillwater Quarry · The Quays · Vortex Citadel · Wild Overgrowth |