Where to catch, #0044
Gloom in Let's Go, Pikachu and Eevee: 5 places, levels 31 to 42
Let's Go, Pikachu and Eevee: the game page
No encounter in Let's Go, Eevee.
5 encounters by area
Places
Route 12, Route 13, Route 14 and 2 more
Other games
Also found in 14 other games
Red and Green (Japan)Red and BlueYellowGold and SilverCrystalRuby and SapphireEmeraldFireRed and LeafGreenDiamond and PearlPlatinumHeartGold and SoulSilverX and YSword and ShieldThe Crown Tundra