In the Great Marsh, you can play the Safari Game, where you can try to catch pokémon without battling.
Location of the Great Marsh
The gate to the Great Marsh is in the north part of Pastoria City.
Check Which Pokémon Can Be Caught
Go upstairs in the Great Marsh building and you can use the binoculars along the north wall to see some of the pokémon that can be caught in the Great Marsh right now.
How to Start a Safari Game
After you go into the Great Marsh gate, you can go north toward the door in the back, and you will be asked to pay to play a Safari Game. The game will continue until you either run out of Safari Balls or you have gone 500 steps.
Be Careful of Bogs
There are some areas of dark mud that you can get temporarily stuck in. Try not to step in them.
How to Catch Pokémon in the Great Marsh
While playing the Safari Game in the Great Marsh, if you encounter pokémon, you can't use your own pokémon to battle. Instead, you can throw a Safari Ball to try to catch the pokémon, or throw Bait or Mud.
Throwing mud makes the pokémon less likely to run away, but makes the pokémon harder to catch.
Throwing bait mades the pokémon easier to catch, but more likely to run away.
Items in the Great Marsh
Talk to the Ace Trainer to the right of the Great Marsh entrance to get some TM97s, which teach Defog.
You can use the Tram near the entrance of the Great Marsh to move quickly to different areas. Use it to go to Area 1 for the following items.
West of the "Area 1" sign, there is a Potion.
In the northwest corner of Area 1, there is a hidden Rare Candy.
North of the Potion, there is a Super Repel.
In the northwest part of Area 2, there is a Great Ball.
To the east of where the Great Ball was, there is a hidden Toxic Plate on a tree.
In the northwest of Area 3, there is a Jar of Honey.
East of that, there is a hidden Ultra Ball.
In the northwest of Area 4, there is a Poké Ball.
In the southeast of Area 4, there is a Super Potion.
In the southern part of Area 5, there is an Antidote.
Northwest of that, there is a hidden Full Heal.
In the northeast of area 6, there is a hidden Nugget.
In the eastern part of area 6, there is a Paralyze Heal.
To the south of the Paralyze Heal, there is a hidden Hyper Potion.