-you get pikachu in the wild, not at oak's lab
-pokemon yellow dosent have a key items pocket
-you dont use eevee againts your rival (unless your talkin bout him USING an eeve then its ok)
The answer was that there is no key items pocket. Oak catches it on the route, but gives it to you in the lab, and the rival uses Eevee.
As for yours:
-Fantina's Mismagius does not have Tackle.
-Route 501 is not in Sinnoh.
-Salamence doesn't learn Tackle.
-Tackle would not harm Ghosts.
-Fantina's Gym is not in Pewter.
-Rayquaza is definitely not found on Route 218.
-Roark is not Canalave's leader; Byron is.
-Byron is not the first leader.
Uh, you realise you're only supposed to have one error, right?
The big battle between me and my friend Jack was on. We decided it would be 3 on 3. I led with Rapidash and he used Roserade. I used Sunny Day, and he tried Toxic, which missed. Rapidash then used a super-effective Flamethrower to KO Roserade. Next Jack used Blissey. Normally, I hate those things, but this time I came prepared. I switched out to Lucario (Blissey used Double Team), and then Lucario nailed Blissey with a Close Combat. Jack's last Pokemon was Dragonite. Lucario tried a Stone Edge, but Jack anticipated it and weakened it with Dragonite's Charti Berry. Dragonite struck back with Dragon Claw, taking out Lucario. I went back to Rapidash, and purely on a whim, used Solarbeam (didn't have to charge cos of Sunny Day). It critted and took out Dragonite! Go Rapidash! :)