Pokemon Yellow In-Game Trade Listings
Introduced in Pokemon Red, Blue and Yellow was the concept of In-Game Training. This is done with a number of non-playable characters in the game, and they can help you along the way. These Pokemon even grow faster than the Pokemon you catch on your own. However, some of the trades aren't really worth wild, if you actually think about the possibility of catching the Pokemon for yourself.
There Are Seven Possible In-Game Trades For Pokemon Yellow:
#1) Mr. Mime On Route 2: The first in-game trade can be found on Route 2 outside the entrance of the Diglett Cave. The Trainer will request in return an Clefairy, which alone can be difficult to find and catch in the wild. However, Mr. Mime can't be found in the wild, meaning this trade is essential in order to complete the Pokedex.
#2) Machoke On Route 5: Just north of the Underground Tunnel Exit on Route 5 is a trainer requesting to trade his Machoke for a Cubone. This is the best trade in the entire game, as the Machoke will evolve into Machamp immediately after the trade and will give you a powerhouse on your Team. Do this trade as soon as you can!
#3) Dugtrio On Route 11: The next trade is found on Route 11 where a trainer is requesting a Lickitung for their Dugtrio. This trade isn't at all necessary since it's easier to find and catch a Dugtrio in the wild than it is Lickitung in Cerulean Cave.
#4) Parasect On Route 18: The trainer is found upstairs in the Gate on Route 18, and is requesting a Tangela in return for their Parasect. Again, not a good trade since both Pokemon can be found in the Safari Zone.
#5) Rhydon In Cinnabar Island: This trainer can be found in the Cinnabar Labs and would like a Golduck in return for his Rhydon. This is a pretty darn good trade, since Rhydon is difficult to find in the wild or train a Rhyhorn to obtain.
#6) Dewgong In Cinnabar Island: This is one of two useless trades in the Labs on Cinnabar Island, where the trainer wants a Gorwlithe in return for Dewgong. Both Pokemon can easily be obtained in-game, but Dewgong can help with Blaine if you absolutely need it.
#7) Muk In Cinnabar Island: Uhh... What...? A Muk that can easily be caught in Pokemon Mansion for a Kangaskhan that rarely is found in the Safari Zone? No thanks. Literally, don't do this, and just catch Muk in the Pokemon Mansion up the road.