You can catch it at the Pastoria Great Marsh.
In the great marsh
You can find it from Great Marsh.
you have to evolve it from scorupi which you get at the great marsh You can also catch it in the great marsh but its only a 10% encounter, i suggest using the binoculars
For a Pokéner to catch a Marill to evolve into an Azumarill,search in either the Safari Zone or Mt. Mortar. The Safari Zone is easier. Marill appear at night in a certain area.
Marill can be found in Pokemon Peal in the Great Marsh area. The Great Marsh let players catch Pokemon not found anywhere else in the region.
in the great marsh but its weak better catch a buizel
You could breed it with another marill, holding a Sea Incense , and in pokemon pearl is Sinnoh, so there's a safari zone, you can catch one there. You can catch it also in Pastoria City's Marsh game areas 1-6 and in the Trophy Gardens. Hope u catch it!
You can catch it at the Pastoria Great Marsh.
In Platinum, you can find it in the Great Marsh.
you go into the great marsh
In the great marsh
After you get the national dex he "might" appear in the great marsh(but he's very rare)
You get tangla in the great marsh
Well, In the Great Marsh. Roselia
Great Marsh (Rare)
at the great marsh in pastoria city