TL;DR: Backstory about always wanting to trade in gen 3 since I was a kid and after 13 years I buy all the things I need to in order to do that. Friend tells me about a cool Vaporeon build that has uses Wish which is special because it requires some particular breeding and trading from Kanto so I buy a refurbished cartridge of Leaf Green and spend about 30 hours doing everything from scratch (aside from already having Emerald completed) all the way to having a Bold Vaporeon with Wish in Emerald.

This thing took forever to get but it was worth it. When I obtained the National Dex on my first playthrough in Emerald as a kid I always wanted Pokemon from other regions but had no access to people/money to trade Pokemon over from FRLG plus I had a DS which can't trade with other GBA Pokemon games so I just dealt with what I had and had fun anyway. Fast forward about 13 years from then to about a month ago when I splurged and bought 2 GBA SPs, a link cable, and a refurbished Pokemon Ruby. For the first time ever I had the ability to trade Pokemon in gen 3 which was super cool to me. It felt like I made kid me proud.

The reason this took so long is because I needed a few things: A Bold Ditto, a female Pikachu, a female Eevee (12.5% to be female), a male Togepi, National Dex in Leaf Green, and access to cross region trading which is obtained from a post game side quest in FRLG. Bold Ditto and female Pikachu were fairly easy to get in Emerald since I got Bold Ditto on my 1st or 2nd try. Female Pichu was obtained pretty quickly and all I had to do was cram vitamins and berries down it's throat and make it feel involved as it leveled up while holding a Soothe Bell. Getting the gift Eevee from Celadon Mansion to be female took under 10 tries and it happens fairly early into the game. To be fair it doesn't HAVE to be female right away but you will need one eventually. The hard part is everything else aside from hatching the gift Togepi egg in the post game which fortunately was a male first try. After getting the gift Eevee the rest of the game was just a normal playthrough. I spent most of the playthrough stressing about the Elite Four since I've never beaten it and remembering how much I got my ass kicked on a Fire Red ROM I played a while back which resulted in me giving up. Lately I've gotten back into Pokemon and with the help of my knowledgeable friend, who also told me about this build, I've had my knowledge of Pokemon expanded even further which is how I know how to EV train, breed for egg moves, which types are/aren't Atk/Sp. Atk, and Im not proud to admit this but also the difference between Atk and Sp. Atk. & Def and Sp. Def. Anyway, before I got to the Elite Four I wanted to make sure my whole party was at least level 50 so I grinded with the VS Seeker for a few hours. By the end of that grind I had a level 50 Snorlax, Kadabra, Venusaur, Jolteon, Lapras, and for my 6th Pokemon I wanted a fire type so I went with Moltres so I could also put Fly on it. I won't bore you with more details about the Elite Four. I beat them my first try with fairly minimal issues between the 26 and 27 hour mark.

Hello post game. Since I had been catching every new Pokemon I came across and evolving Pokemon throughout the game I easily got 60 Pokemon which is what you need to get the National Dex from Professor Oak in FRLG. Then I went off to One Island to start Celio's quest which is what is required to trade with Emerald. That quest probably took around 2-3 hours of exploring and island hopping with some battles in between. Then at long last the 30 hour step of completing Leaf Green and Celio's quest was over and all that was left was trading the (now) Jolteon and Togepi over to Emerald and the breeding.

At this point in the story it just occurred to me I haven't explained the reason for why a female Pikachu and male Togepi are needed. Togepi, more specifically Togetic when it's evolves, learns the move Wish. Togetic and Pikachu share similar egg groups so they can breed with each other. The reason Pikachu has to be female is because I wanted a male Pichu and the species of a Pokemon is determined by the mother and since Wish is an egg move the baby will be a Pichu with Wish 100% of the time. So now that I had a male Pichu w/ Wish I had to evolve it into Pikachu to breed with the female Jolteon for an Eevee with Wish. Then for the final breeding step I just needed to breed that Eevee with a Bold Ditto holding an Everstone for a Bold Eevee with Wish then rub a Water Stone on it.

This whole process was long but I learned a lot so now I have more Pokemon knowledge and a dope Vaporeon on my Emerald. Wish with Protect is really cool since Wish heals Vaporeon after the next turn so if you use Wish then Protect you'll get a guaranteed heal. Then of course after all of this I still went through with EV training it in HP/Def. Bonus EV training tally mark sheet on 3rd slide.