In order - FRLG FAQ, Ruby/Sapphire Plates - The Ultimate Guide of Getting Them, Pokemon Choice Guide, FR/LG Hidden Items Guide.
Fire Red/Leaf Green FAQ
Credit to Trip and TRJessie579 for the original FAQ, and Chaos Emerald for edits/additions.
Note: This thread is not for short, one-liner questions. Use the Official Help Thread for that. This is mainly for discussion of things that don't fall under any other category.
FAQ
Q: FireRed and LeafGREEN? Why didn’t they make Blue instead?
A: Red and Green were actually the original two Pokemon games, in Japan. Then Pokemon Blue came out, and our Red and Blue games were based on Japan’s Blue. Blue had improved graphics over Red and Green, different Pokemon locations, etc. Note that it also had a different Cerulean Cave design, which the American RB was based on, while FrLg's was based on the original Japanese RG, which is why FrLg's Cerulean Cave has a different layout than RB's.
Q: What are the differences between these games and the old ones?
A: FireRed and LeafGreen are in the same generation as R/S/E, so they have the same Pokemon info—Natures, Abilities, shinies, genders, breeding, etc. Some Pokemon locations and Pokemon you trade for have been changed, and obviously the graphics are much better than they were in Red/Green. Also, all 386 Pokemon can be used in this game, though they can’t necessarily all be obtained.
The most major change from the old to the new games is the addition of the Sevii Islands, which will be discussed later in the FAQ.
Q: Is there day/nighttime in this game?
A: No, there isn't an internal clock, so no day/night of any kind exists. This also means you cannot get Espeon and Umbreon.
Q: What is the VS Seeker and where do I get it?
A: The VS Seeker allows you to rebattle field Trainers. This does NOT include Gym Leaders, or Trainers in buildings or caves. Once you use the VS Seeker, you must take 100 steps to “recharge” it and be able to use it again. You get the VS Seeker from a woman in the Vermillion Pokemon Center.
Q: Where do I get HM ___?
A: HM 01 Cut: You get this once you help the seasick Captain of the SS Anne in Vermillion City.
HM 02 Fly: This can be found on Route 18, West of Celadon City, by using Cut on a tree above the Bike Path. You will come to a house with a girl in it that will give it to you.
HM 03 Surf: In the Safari Zone’s Secret House.
HM 04 Strength: If you find the Warden’s Gold Teeth in the Safari Zone and return them to him, he will reward you with this.
HM 05 Flash: If you have at least 10 Pokemon in your ‘Dex, go to a building on Route 2, below Diglett’s Cave. One of Professor Oak’s aids will give it to you.
HM 06 Rock Smash: In Ember Spa, on One Island.
HM 07 Waterfall: In Icefall Cave, on Four Island.
HM 08 Dive: This HM is not obtainable in this game, only in R/S/E.
Q: Why won’t the Saffron City guard take my Fresh Water?
A: To prevent people from getting into Saffron early by trading in a Fresh Water, they’ve changed the item you need to give to the guard. On the first floor of the Celadon Mansion is an old woman who will give you the “Tea” item. This is what the guard will accept to let you pass.
Q: Where is the Move Deleter in this game?
A: Fuchsia City, in between the Pokemon Center and the Gym.
Q: My Golbat/Chansey stops evolving even when I didn’t press B! What’s going on?
A: Since Crobat and Blissey are Johto Pokemon, they can’t be obtained until you have the National Dex. Once you get it, your Pokemon will evolve.
Q: How do I get the National Dex?
A: After you beat the Elite Four, if you have 60 or more Pokemon caught in your Pokedex, you will get the National Dex automatically. If not, get 60 Pokemon and then go talk to Oak, he will give it to you.
Q: Are there more Johto Pokemon in this game?
A: Yes, once you have the National Dex you can go to Four Island and the rest, which have Johto Pokemon running around.
Q: How do I get the Leftovers/Macho Brace/Soothe Bell?
A: In FR/LG, these are items you can only get in a special way. You have to stand on a specific spot and use the Itemfinder. It will tell you that an item is “buried” underneath the ground, and will unearth it for you. The Leftovers is located under both Snorlax, the Macho Brace under Giovanni in the Viridian City Gym, and the Soothe Bell under Mr. Fuji in Lavender Tower. Remember that you have to stand on the EXACT SPOT they were on and use the Itemfinder to get the item.
Q: I went with Bill to the Sevii Islands and now I’m lost. What do I do?
A: Before you can go back, you have to save a girl on Three Island, in the Berry Forest, from a Hypno. Once you do, and talk to her father on Two Island, you can go back to Kanto.
Q: Why isn’t Moltres in Victory Road?
A: It’s been moved to One Island in this game. Just go North to Mt. Ember to find it.
Q: How do I get the woman on Two Island to teach my starter a special move?
A: First, you need a Venusaur, Charizard, or Blastoise (it does NOT have to be the Pokemon you started with). Next, this starter must be at MAX happiness, or she will not teach it the move. Finally, put it in the first slot of your party and talk to the woman. She will teach Venusaur Frenzy Plant, Charizard Blast Burn, and Blastoise Hydro Cannon. You can teach each starter this move ONCE, per game (so you can have the woman teach a Venusaur, Charizard, AND Blastoise their special moves, not just one).
Q: Does this game have a Move Tutor like R/S/E?
A: Yes, and he is on Two Island. Instead of taking Heart Scales like in R/S/E, he takes either two Tiny Mushrooms or one Big Mushroom. These items can be found on wild Paras and Parasect.
Q: How do I get this Egg on Five Island, and what’s in it?
A: If you Surf North from Five Island, you will find a man who will offer to give you an Egg. If you have a free space in your party, and your lead Pokemon is at MAX happiness, you’ll get the Egg, which contains a Togepi.
Q: What does this “Tanoby Key” on Seven Island open?
A: If you solve the puzzle, it will open the Tanoby Ruins at the very South of Seven Island, which contain the Unown. Each cave has different Unown in it, so you’ll have to visit all of them if you want to get all the Unown. Unfortunately, you get absolutely nothing from capturing all 28 Unown except for the satisfaction of having wasted precious time of your life.
Q: How come I can’t breed in the Daycare in Cerulean City?
A: This Daycare is set up just like the one in the original games. The Daycare where you can breed is on Four Island.
Q: How do you get through Lost Cave, and what do you get?
A: Count the number of rocks in each room, then picture the room as a clock and go into the corresponding door. Three rocks, you go right; six, you go down; nine, you go left; twelve, you go up. This will lead you to Selphy, who will return to Resort Gorgeous. Going through other doors may lead you to items. If you go to visit Selphy, she’ll ask to see a random Pokemon. If you can bring it to her, she’ll reward you with an item, most often Luxury Balls, but sometimes Nuggets, Pearls, and other things of that nature.
Q: I’ve heard that the E4 gets stronger the second time you battle them! Is that true, and if so what’s different about them?
A: Yes, this is true—when you fight the E4’s “second wave,” their Pokemon are higher levels (from 10 to 12) and some have changed their teams around. Lorelei replaces Slowbro with Piloswine. Bruno's Onix is now a Steelix. Agatha's Golbat evolves and Haunter is replaced with Misdreavus. Lance evolves one Dragonair and replaces the other with Kingdra. Your rival replaces Pidgeot with Heracross and Rhydon with Tyranitar.
Q: How do I get Mewtwo? The guy won’t let me into Cerulean Cave!
A: Before you can get into the Cave, you need to have beaten the E4 for the first time, obtained the National Dex, and fixed the Network Machine. Only then will you be able to go in and capture Mewtwo.
Q: Huh? My Pokemon came back to me when I tried to release it! How do I get rid of it?
A: This doesn't have to do with happiness, as the game might suggest (____ came back! Was it worried about you?), but HMs. If the Pokemon you're releasing is the only one you have with Surf (and this also seems to work on occasion with Waterfall), it can't be released. Teach another random Pokemon Surf, then try again.
Q: The guy at the daycare says my Pokemon don't like each other! Why? Will they breed?
A: Yes! The message that you'll get when the Pokemon are not compatible is "They prefer to play with other Pokemon." The phrase, and how many steps it takes to get an Egg, depends on your Pokemon's species and trainer ID number.
Different IDs and Same Species = Fast "The two seem to get along very well."
Different IDs and Different Species OR Same IDs and Same Species = Medium "The two seem to get along."
Same IDs and Different Species = Slow "The two don't seem to like each other."
Q: How do I get Upgrade/Metal Coat/King's Rock/Dragon Scale so I can evolve my Pokemon?
A: Up-Grade - On Five Island in the Rocket Warehouse. Use the floor with the arrows to get to the room at the top left of the Warehouse, it's in there.
Metal Coat - On Five Island at Memorial Pillar. From Five Island Surf down as far as you can and you'll come to a small piece of land with a statue on it. The Metal Coat is below the statue.
King's Rock - On Seven Island in Sevault Canyon, you need Strength and Rock Smash to access it.
Dragon Scale - On Six Island in the Water Path. From Six Island walk North until you come to water where you can Surf. Then Surf south along the side of the island to come to the item.
All four of these are also prizes from the Trainer Tower on Seven Island.
Q: How do I encounter Raikou/Entei/Suicune? (thanks to LordKelvin for suggesting)
A: You can only encounter one per file, and it depends on which starter you pick:
Bulbasaur-Entei
Charmander-Suicune
Squrtle-Raikou
They're running around the Kanto mainland after you get the National Dex (that means no Sevii Islands) and it's random what route they're on. Once you find one or get the data for it through trading, you can track it by checking its route, but if you Fly or turn off your game, its route is re-randomized. Note that if you don't plan on using a Masterball, unless you're facing Suicune, DO NOT use Wobbuffet or a Pokemon knowing Mean Look/Block/Spiderweb. Raikou and Entei know Roar, and if they use it, they'll disappear exactly as if you defeated them. Also worth noting, a glitch in the IVs of running Pokemon in the 3rd generation causes any of them to have 4-5 IV's that are all 0-1, so if you have Colosseum, it's a much better idea to get them from that game. Here's a tip for finding them from Shiny Trainer:
Go to route between Celadon & Saffron (Route 7) while having a Level 30-49 Pokemon as the first Pokemon in your team, along with a bunch of Repels.
Use the repel, and search the grass. If the repel runs out and you haven't found the Beast, go to Celadon, use repel, return to the grass and search again, and keep doing it until you find the Beast. Throw your Masterball, and it's yours 
Q: Where is the Move Deleter?
A: In Fuschia City in a house next to the Pokemon Center.
Q: Help! I went to face the Elite Four a second time but Lorelei isn't there! Is my game glitched?
A: No, you need to finish some Sevii Island quests first.
Q: Can I evolve Eevee into Espeon and Umbreon in this game?
A: No. In Fire Red and Leaf Green (as well as Colosseum), you can only evolve your Eevee into Vaporeon, Jolteon, or Flareon. You can obtain an Espeon or Umbreon by trading Eevee to Ruby, Sapphire, or Emerald, raising its friendship, and raising a level (between 12 PM and 12 AM for Espeon, between 12 AM and 12 PM for Umbreon). You could also trade it to XD and use the Sun Shard (Espeon) or Moon Shard (Umbreon), provided you have not used up your one-per-game Eevee-evolution item.
Q: Can this game trade with all the other versions?
A: Fire Red and Leaf Green can trade between each other as soon as you have the ability to trade, but any other game can only be traded with after you get the Ruby and Sapphire to Celio, plus finishing any requirements in the other game you are trading with.
Q: Which game is better/how are they different?
A: The only difference between these two games is the obtainable Pokemon.
In Fire Red, you can get Ekans, Arbok, Oddish, Gloom, Vileplume, Bellossom, Psyduck, Golduck, Growlithe, Arcanine, Shellder, Cloyster, Electabuzz, Elekid, Scyther, Scizor, Wooper, Quagsire, Murkrow, Qwilfish, Delibird, Skarmory, and Attack Deoxys (event-only). You can also do an ingame trade of Nidoran M for a Nidoran F, and Nidorino for Nidorina. There are also some Pokemon that are less common or more common than in Leaf Green, but they can be gotten with patience.
In Leaf Green, you can get Sandshrew, Sandslash, Vulpix, Ninetales, Bellsprout, Weepinbell, Victreebel, Slowpoke, Slowbro, Slowking, Staryu, Starmie, Magmar, Magby, Pinsir, Azurill, Marill, Azumarill, Misdreavus, Sneasel, Remoraid, Octillery, Mantine, and Defense Deoxys (event-only). You can also do an ingame trade of Nidoran F for Nidoran M and Nidorina for Nidorino. There are also some Pokemon that are less common or more common than in Fire Red, but they can be gotten with patience.
So choose which game based on those factors.
Q: How do I clone in the 3rd generation?
A: Check the Cloning in Emerald thread.
Q: What's with the old lady on Seven Island that has the boxes in her house? Can I get behind them or something?
A: Short answer: No, most likely not. Long answer: It was used in the Japanese versions of Fire Red and Leaf Green to fight trainers that you downloaded using Battle-e Cards. The e-Reader was discontinued in the rest of the world due to lack of popularity, so the feature of connecting was removed, but the data to go to the spot still exists. So if you happen to have a Japanese FrLg, a Japanese e-Reader, and some Japanese Battle-e Cards for FrLg, you can go there. But it's really pretty pointless anyway (if you have the Battle-e Cards for Ruby and Sapphire, it's pretty much the same deal).
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RUBY AND SAPPHIRE PLATES
The Ultimate Guide of Getting Them
By Dramatic Melody
So I took the near-impossible task of creating a guide on how to get the Ruby and Sapphire plates. I’ve seen millions of threads created about it, and I hope this guide would lessen that…somehow.
There will be four parts in this guide: Prerequisites, Getting the Ruby Plate, Getting the Sapphire Plate and After the Work. The parts will hopefully explain everything and anything you need to know about this simple but complex post-credit quest.
So let’s get started, shall we?
PREREQUISITES
Before you actually begin your quest for the two plates, you must’ve done three things first, which I will list here:
1) Beat the Elite Four
– Of course, it is a given that you will have to beat the Elite Four (and the Champion) at least once, as this is a post-credit quest, and the only way for the credits to roll is if you beat Lorelei, Bruno, Agatha, Lance and your Rival.
– As a side-note, while you are doing this quest, you will not be able to fight the Elite Four, since one of them, Lorelei, is part of the quest. You’ll be able to fight them again after you’ve done the quest, as explained in the “After the Work” section.
2) Obtain the National Dex
– After beating the Elite Four, you must then obtain the National Pokedex from Professor Oak, which he will give if and only if you have caught sixty (60) Pokemon from the FR/LG Pokedex. That’s right, not seen – CAUGHT.
– The FR/LG Pokedex refers to the first 151 Pokemon of the National Pokedex, which are the only obtainable Pokemon within the game prior to this quest and without trading with other games (barring Mew and version exclusives), which is impossible without the Ruby and Sapphire plates anyway.
3) Finish the first Sevii Island Quest
– While this can be done before beating the Elite Four (to be precise, after you beat the seventh gym, Blaine), it is still put here since it is an important prerequisite. You must have finished the first quest involving the first three islands, namely: Meet Celio in One Island, Beat the Goons in Three Island, Rescue Lostelle in Berry Forrest, Return her safely to her parents in Two Island, give the meteorite to Bill and receive the Tri-Pass from Celio. Sounds like a lot, doesn’t it?

Yeah, it looks like a long list (of three), but they’re simpler once you actually do it. Honest. 
GETTING THE RUBY PLATE
Yay. The easier of the two plates.
You must have done the three things under “Prerequisites” before you do this.
I’ll put them in chronological order, for your convenience. 8D
1) Go to One Island and Talk to Celio.
– He’ll tell you about his plans of upgrading his machine, but then he says that he needs your help in retrieving an important part – the Ruby plate.
– His hunch is that it’s somewhere in One Island, but he’s too lazybusy to find it and “politely” asks you to do so. Being the all-around nice guy/gal, you agree.
2) Go up to Mt. Ember, Defeat the Rockets, and Retrieve the Ruby
– When you enter Mt. Ember, go right, and you’ll see two Rocket Grunts in front of a cave opening. You’ll overhear one of the passwords, “Goldeen need log”, but before the grunt proceeds to say the second one, they spot you and both challenge you to two separate single battles.
– After defeating them, they’ll run, and you’re free to enter the cave. I unfortunately do not remember how to go through this cave the proper way, but I do know that you’ll need the HM Strength, and at the end, you’ll get the Ruby Plate. Yay!
3) Give the Ruby to Celio and Get the Rainbow Pass
– Give the Ruby plate to Celio, and he’ll plug it in inside his machine. A red dot will appear on the left, and he’ll rejoice.
– He will then “politely” ask you again if you can finish the job by retrieving yet another important part – the Sapphire Plate.
– When you accept (of course you will), he’ll give you the Rainbow Pass, which will give you access to Four, Five, Six and Seven Islands.
And that’s all for the easier plate. Now, for the harder of the two…
GETTING THE SAPPHIRE PLATE
Getting the bluer and cooler of the two plates is much, much harder than the other one, and it is way, way longer and more complicated.
This part is probably the reason why you’re viewing this, amirite?
You must have done all three steps under “Getting the Ruby Plate” before you can begin with the first step.
Ready?
1) Go to Four Island and Defeat the Grunts in Icefall Cave
– With your newly-acquired Rainbow Pass, take the ship to Four Island and go inside Icefall Cave. After doing the mini-quest of Icefall Cave (which involves getting the HM Waterfall), climb up the Waterfall and go inside specific cave entrances. At the end, you’ll meet Lorelei (the first of the Elite Four you battle, the one that uses Ice Pokemon) and three Rocket grunts.
– After some exchange of dialogue, Lorelei will then tell you to defeat one of the grunts while she takes care of the other two. Do that, and they’ll all flee afterwards. Lorelei will then thank you and tell you about her desire of keeping her hometown in peace. After doing that, you can proceed to the next step, which is…
2) Go to Six Island, Open Ruin Valley, and Watch the Sapphire Plate get Stolen
– Go to Six Island and surf southwards. After a few battles, you’ll reach the entrance of a cave. There’s Braille on the entrance of this cave (which was blocked prior to doing the first step), and it says “Cut”. Let a Pokemon use Cut to get in.
– Fall down the hole. There will be Braille in every room you fall down into, which will tell you which hole you should fall down in next. In order, it is up, left, right and, finally, down.
– If you did that correctly, you should be in a room with a pretty blue gem in the center. Yeah, the Sapphire Plate. Press A to get it and leave…
– After you Press A, a scientist will suddenly fall down from the roof and get the Sapphire Plate (because of your pathetically slow hands). As a way of apologizing (o.O), he gives you the second password, “Yes, nah, Chansey”, and leaves.
– With the two passwords, there’s really only one thing to do…
3) Go to Five Island, Open the Rocket Warehouse, and Get the Sapphire Plate
– Go to Five Island and go east. Stand outside the Rocket Warehouse entrance and press A, which will let you enter the two passwords and let you in. Yay?
– Defeat all the rockets inside and defeat their “leader”. Go up and defeat the stolerScientist, which prompts him to give you the Sapphire Plate he stole. Yay!
– Fly back to One Island and give the Sapphire Plate to Celio. You’re done! YAY!
You can go rejoice now. Or you can read on further for additional stuff you might wanna check out after doing the quest…
AFTER THE WORK
After you’ve done the quest (or certain parts of it), FRLG gives you a few more stuff to explore, adding to its massive replay value. Listed below are these “stuff” that I’m talking about…and no, they are not arranged in any order. =P
Trade with Other Games
– Since Celio’s machine now fully works, you can now trade with any game within the Third Generation. You can now transfer Hoenn Pokemon in your FRLG game, and you can send Kanto Pokemon to your other games. ^_^
Catch New Pokemon
– While you’re doing the quest, you might notice that you’ll see Pokemon outside of the original 151. That’s because the Sevii Islands are filled with new Johto Pokemon that was previously uncatchable in RS. With the National Dex, you can freely catch them to your heart’s content. :P
– For a complete list of Pokemon you can now obtain, click
here.
Battle the Improved Elite Four
– After you finish the quest, Lorelei goes back to the Pokemon League and is now ready to accept your challenge. But she, along with the rest of the Elite Four (and the Champion), now has new and improved Pokemon!
– All their Pokemon have raised ten levels (which now puts the range between 61 and 73), and some Pokemon have evolved or have been replaced by Johto counterparts. This is the best training ground in all of 3rd gen, so have fun!
Explore Cerulean Cave
– Remember the cave back in Cerulean City that was blocked by some dude? Well, the dude’s gone, and you can now go inside Cerulean Cave. It’s filled with the highest-leveled non-legendary Wild Pokemon in the whole game, and, of course, there’s the popular purple legendary – Mewtwo.
And that’s it for this really long guide! I hope it answers all your questions about getting the plates, and I hope it’ll make that quest easier! ^_^
~> DM
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