Cheats, Codes & FAQs
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Determining Pokemon's feelings towards you.
When you use an item on one of your Pokemon outside of a battle, such as a Potion, the Pokemon will either move closer or away from you in the short intermission sequence. How far the Pokemon moves depends on how much it likes you. If it does not move at all, it feels neutral.
Ditto Breeding
You don't need to find one pokemon of each gender in order to breed them. You simply have to put your pokemon of choice and a ditto into the daycare center. After a short while, the old man will tell you that they found an egg, and when it hatches, it will be whichever pokemon you matched up with Ditto
Easy money
On Island 5, there is an area to the northeast called Gorgeous Resort. There are 2 wealthy trainers you can face. They are named Lady Jacki and Lady Gillian. Lady Jacki gives you $10000 if you beat her($20000 with Amulet Coin) and Lady Gillian gives you $9800($19600 with Amulet Coin). The pokemon they use also carry expensive items. Jacki's 2 pokemon carry Stardust, Gillian's 2 Mareep have Stardust, and Gillian's Flaafy has a Nugget. Just use Thief or Covet to obtain these items.
Free Coins
In the Gamecorner in Celadon City, go talk to the man at the far right Slots. He will give you 20 free coins. Talk to the man on the slots beside him. He will give you 20 free coins, also. Go to the left side of the Gamecorner. Talk to the guy that looks like a fisherman, and he will give you 10 free coins.
Loose change in Game Corner
Apparently, the folks in the Game Corner don't hold on to their coins very well!
By using the Itemfinder or looking by yourself, you'll find that many spots in the Game Corner have some number of coins lying on them. If you find them all, you'll find 200+ coins!