I'm sure we have all heard of the glitch for catching mew, and if you haven't feel free to look it up online, because I don't want to explain it here.

so imagine that every trainer on red blue and yellow is a guardian of a single pokemon.
the way to battle these pokemon is to fly from the gambler between saffron city and lavender town, and battle the trainer.

most people know of the jr. trainer with a slowpoke, so imagine he is the guardian of mew. fly from the gambler, and battle the jr trainer, then fly to lavender to battle the pokemon at level 7. I found that the trick works for every trainer, but the pokemon is different according to the trainer.

I have been recording the trainers and their protected pokemon

so here is what I have found so far;
trainers north of cerulean:
jr. trainer (slowpoke)-mew (yes its real)
hiker north of cerulean-Nidoqueen
jr.trainer (rattata/spearow)-Nidoqueen

fighting dojo:
first trainer-psyduck
second trainer-Mr.Mime
third trainer-Electabuzz
fourth trainer-psyduck

Bikers east of celdon:
biker just below entrance-hitmonchan
cueball (mankey/machop)-pinsir
cueball (machop/mankey/machop)-pinsir

Rockets in saffron:
rocket directly in front of the stairs of floor 2-pinsir
rocket after rocket above (cubone/zubat)-missingno
rocket brother (take telepad to left of floor 2)-hitmonlee

this is a work in progress list, and I plan to update it as I continue my finds, but I wonder if the values are different for every game version, or even every game, or if the trainers all share the same list of trainers and their "secret pokemon"

I am using red version for these tests, and I need help mapping this out, and discovering if my trainers have different secret pokemon than yours.

process: Save directly in front of the pass from saffron-lavender to celdon-saffron. walk down while hitting the menu so that the menu appears before the gambler underground sees you. use fly, and as you fly the gambler will have an "!" appear, but then you fly away. fly to the town closest to the target trainer. when battling the trainer be sure to enter his/her line of sight so that they walk to you, if you walk directly in-front of them the game will freeze. your menu button won't work until you defeat a trainer. after defeating the trainer, use fly to fly to lavender town. walk to the east as if exiting the town, and one of two things will happen:
1)the menu opens, close it to battle the pokemon at level 7
2)a chat box appers saying,

press a for the box to close, and the battle will take place (the pokemon is at lv.7)

catch the pokemon if you want, but be sure to stock up on great balls, pokeballs, and ultras, because some of the pokemon will only be caught with a pokeball, or only a great ball, or only an ultra ball. haven't tested with master ball yet)

if you find anything, please post it here, so we can add to our findings, and thanks in advance
-Nabkov

I tried that glitch before and got Mew so I know that glitch works (Blue). But I kept trying in my Blue game and I did that same glitch with the Gambler and battled other trainers too.

One time, I found Shellder, another I found Growlithe, and the other time, I found another Mew. But then, something really.... strange happened. I did the glitch, and when I walked to exit Lavender Town, someone said something and I was battling. So I beat that person,(I couldn't tell what type of trainer it was), and I had started a New Game and only had like Level 21 Pokemon. So another battle started after the first and my Pokemon were almost fainting because my opponents Pokemon were around Level 25. So next, another battle started and I won.

But, the weirdest thing that happened were:
#1. I couldn't see the type of trainer I was battling(the sprites were messed up like Missingno.)
#2. The battles were consecutive(no break, just one after the other)
#3. The Pokemon were the same
#4. The trainers said different thing each time.

So that's what happened when I tried the Mew Glitch multiple time. Sorry for not knowing what Trainers I had battled then. But I am posting this as something you can add to your findings. Thanks.

thank you for the informantion, and I have more data now!

Bikers west of Celdon city:
Biker (weezing)-dragonite
Cueball (machop)-growlieth
Biker (grimer/grimer/grimer/grimer)-pinsir
Cueball (machop/Machoke)-kadabra
Biker (weezing/koffing/weezing)-mankey
Cueball (mankey/primape)-hitmonchan
Biker (muk)-electabuzz
Biker(weezing/muk)-psyduck
Cueball (machop/mankey/machop)-pinsir
Biker(koffing/weezing/koffing/koffing/weezing)-magmar

Bird keepers west of Fuchsia:
Bird keeper (spearow/fearow)-arbok
Bird keeper (dodrio)-magmar

Fuchsia gym:
Juggler (hypno)-omanyte
Juggler (drowzee/kadabra)-horsea
juggler (drowzee/drowzee/kadabra/drowzee)-venonat
Tamer (arbok/sandslash/arbok)-electabuzz

bug catcher north of vermillion (weedle/caterpie/weedle)-grimer

hope this helps anyone else attempting this

i dont know if this is know but, the first JR trianer outside of fushia city heading east in yellow gives off a missigno.

Hey, you found out how to manipulate the Mew glitch! Good for you! I've got a more in-depth look at this here.

But it's kinda complicated. Hex is involved!

After you initiate the glitch by flying away from the Gambler, just find a Ditto and have it transform into whatever pokemon you have first in your party.

The pokemon that you encounter when walking left of Lavender Town, right of Saffron City, depends on what number is your first pokemon's special stats.

The Slowpoke in Cerulean City that you need to beat apparently had his Special Stat at 21. 21 = Mew.

(I've used this glitch myself on my Red Version, and on my Yellow Version Emulator.)

The only difference between the two versions is that I successfully got all 151 pokemon thanks to the glitch and nothing was messed up.

On the Yellow Version Emulator, I did the glitch so many times, that when I stopped, I went to catch a Clefairy in Mt.Moon. Caught it. Went to Celadon City to get the Clefairy from my PC and train it.. turns out it was a Pink Wartortle. No joke. a PINK Wartortle. A few minutes later, after using said Pink Wartortle, my game crashed on itself and I had the dreaded 'NEW GAME'.. =[

So yeah.. I guess you kinda have to be careful or something. >_>