Where to catch, #0086
Seel in Diamond and Pearl: 2 places, levels 35 to 45
2 encounters by area
Places
Sea Route 226 and Sea Route 230
Other games
Also found in 12 other games
Red and Green (Japan)Red and BlueYellowGold and SilverCrystalXDFireRed and LeafGreenHeartGold and SoulSilverBlack and WhiteBlack 2 and White 2Ultra Sun and Ultra MoonLet's Go, Pikachu and Eevee