Violet City is the first city you'll visit that has a Gym in it. You don't want to rely on just one Pokémon for a Gym Leader battle, so you'd better catch and raise some wild Pokémon to fill out your party (especially if you picked Chikorita as your starter). You won't be able to reach the items above the city until you have Surf.
Trade your Bellsprout for an Onix
You can catch an Onix later, but you'll never get as much use out of one as you will now versus Falkner and his Junior Trainers. Visit the house southwest of the Pokémon Center with an extra Bellsprout in order to trade it for an Onix. As a traded Pokémon, your Onix will go up levels more quickly than a wild one, but you're stuck with the goofy name. Like all trades with computer characters, its starting level will be the same as that of the Pokémon you traded for it. To get the Onix with Rock Throw, train your Bellsprout to level 14. However, if you plan to use Onix in the first gym, do not let it get over level 9 or it will start disobeying you.
Back to Pokémon School
If you talk to the man standing between the Gym and the Mart, and answer "No" to the question he asks you, he will lead you down to his Pokémon Academy to study up on Pokémon types and conditions. In this schoolhouse, he teaches his students some basic Pokémon battling and raising lessons. You can also learn a lot from the writing on the blackboard and the other students. Study hard!
There are a lot of new items for sale, but nothing you really need (X Items are rarely worth it). The last item is mail for writing short messages.
If your Pokémon are too weak for the Gym, build up some EXP at the Sprout Tower first. Sprout Tower is a good place to train your Pokémon and yourself. There is an opportunity to catch your first Ghost type Pokémon, Gastly as well. If your Pokémon are over Level 10, the battles against the Grass-type Trainers won't be very difficult. If your Pokémon aren't at Level 10, it might be a little harder—unless you started with Cyndaquil.
Gym Battle 1: Falkner 
|Bird Keeper Abe: 216
|Bird Keeper Rod: 168|
|Leader Falkner: 900|
It's your first Gym battle, so be careful. There are two Gym Members and one Gym Leader for you to fight, but you don't have to fight them without a break. If your Pokémon get too weak, take them to the Pokémon Center and heal them between battles, so they're able to continue.
Since there hasn't been a chance to get any Electric Pokémon yet, your best bet here is Rock, by far. It has protection from both Flying and Normal attacks, and if you have Rock Throw (Geodude gets it at level 11), it'll wipe out any of Falkner's Flyers. Jigglypuff is also useful because it learns Rollout at level 15.
But you still need to look out for Pidgey's Mud-Slap; it does damage and lowers Accuracy, and the penalties add up quickly. Swap in a strong Pokémon that can finish this Flyer quickly, but watch out for its Gust. However, if you swap in a flying-type or any other type that has a resistance to the move, Falkner may not be able to react quickly enough. One suggestion is to use your recently acquired Onix to screech the Pidgey and Pidgeotto to low defense, then switch out to a flying type and quickly defeat it.
When you beat Falkner, he will award you the Zephyr Badge and TM 31, Mud-Slap. Mud Slap is a move that performs offensively and defensively; it attacks the foe and lowers the foe's accuracy. Remember, you can use a TM only once.
An urgent call from Professor Elm
After you beat the Violet City Gym Leader, you'll get a surprise phone call from Professor Elm. He'll direct you to speak with his aide at the Violet City Pokémon Center, who will give you the Mystery Egg that you delivered to Elm earlier. It needs to be near active Pokémon to hatch. Keep this egg in your party as you continue your quest, and after an hour or so of traveling, it will hatch. That miraculous event is covered on Route #34.
Return later on for stray items
If you examine the map of the city, you'll notice two ponds. Surf across them, and you'll find a hidden PP Up and a Rare Candy on the other side. Don't miss these rare and valuable items!
- PRZCureBerry (on the berry tree near Route 32)
- PP UP (Surf on lake behind Gym)
- Rare Candy (Surf on lake behind Pokémon School)
- Hyper Potion (Use Cut and Itemfinder in the dead end path to the right of Earl's Academy)
|Old Rod||Good Rod||Super Rod|
|#95 Onix||#58 Growlithe|
It now learns most of its good moves at lower levels than it did in Red/Blue/Yellow such as its first Rock type move Rock Throw now at level 14, Rage at level 27 and it can learn new Rock type move Sandstorm at level 36, a move that deals damage to non-Rock Pokémon every turn. Gets Normal type move Slam at level 40.
But the real excitement is that it can now evolve into a new Pokémon, Steelix. This evolution raises most of Onix's stats (except Speed) to competitive levels. But opens up weakness to Fire types.
Onix is a good defensive Pokémon which will be useful for the first two Gyms and get bonus EXP.
Can be taught HM 04 Strength and Fighting type move Rock Smash from TM 08 as well as Ground type moves Earthquake and Dig also from TMs.
First chance at a wild Fire type you don't want to miss. It uses Normal type move Roar to make you run from Battle quite often, so you need to try put it to Sleep.
Has Dark type move Bite and its first Fire type move Ember comes at level 9. With a second Fire type move Flame Wheel at level 34 and is able to learn Fire Blast from a TM.
Has even Physical Attack and Special Attack stats and pretty good Speed stat.
Growlithe's evolved form, Arcanine, is argued as one of the best Fire Pokémon in the game and has high stats where it counts.
One thing to note: Growlithe learns hard hitting Flamethrower at level 50 and Arcanine learns only one move after evolving which is ExtremeSpeed, a new powerful Normal-type attack at level 50 so evolve it with the Fire Stone the moment it learns Flamethrower to get both.