Mt. MoonFireRed&LeafGreen
"Your first real dungeon crawl. Team Rocket is digging for fossils, and you pick between the Dome Fossil and Helix Fossil before leaving. Stock up on Repels."
MT. MOON MAP
Pokemon Encounters
Clefairy is the rare one at 1% on the upper floor and 6% deeper in. Paras at 5-15% is worth the catch too, and Geodude at 25-30% gives solid Rock-type coverage this early. Zubat fills everything else.
Paras
Also found in 1 other location
ITEMS
Pick one fossil on B2F: Dome or Helix. Bullet Seed (TM09), Thief (TM46), and a Moon Stone are the other key grabs. Hidden Rare Candy and a second Moon Stone reward Itemfinder users.
TM09 Bullet Seed
Bullet Seed hits 2-5 times per turn used.
TM09 Bullet Seed
Bullet Seed hits 2-5 times per turn used.
TM46 Thief
Thief deals damage and steals the target's held item, if the user is not holding an item.
Rare Candy
A candy that is packed with energy. It raises the level of a Pokemon by one.
Antidote
A spray-type medicine. It heals one Pokemon from a poisoning.
Dome Fossil
A fossil of an ancient, seafloor- dwelling Pokemon. It appears to be part of a shell.
Escape Rope
A long, durable rope. Use it to escape instantly from a cave or a dungeon.
Helix Fossil
A fossil of an ancient, seafloor- dwelling Pokemon. It appears to be part of a seashell.
Moon Stone
Evolves a Nidorina into Nidoqueen, a Nidorino into Nidoking, a Clefairy into Clefable, or a Jigglypuff into Wigglytuff.
Paralyze Heal
A spray-type medicine. It heals one Pokemon from paralysis.
Potion
A spray-type wound medicine. It restores the HP of one Pokemon by 20 points.
Revive
A medicine that revives a fainted Pokemon, restoring HP by half the maximum amount.
Star Piece
A shard of a pretty gem that sparkles in a red color. It can be sold at a high price.
Big Mushroom
A large and rare mushroom. It is very popular among certain people.
Ether
Restores a selected move's PP by 10 points for one Pokemon.
Moon Stone
Evolves a Nidorina into Nidoqueen, a Nidorino into Nidoking, a Clefairy into Clefable, or a Jigglypuff into Wigglytuff.
Tiny Mushroom
A small and rare mushroom. It is quite popular among certain people.
TRAINERS
Rockets join Hikers and Bug Catchers across the cave. 11 fights total, nothing above level 14, but the back-to-back battles drain your PP and potions fast.
Kent
Mt. Moon Guide
Dome Fossil gives you Kabuto (Rock/Water), Helix Fossil gives you Omanyte (Rock/Water). Both revive at level 5 on Cinnabar Island. Kabuto is the faster attacker, Omanyte is bulkier. Neither changes the game much since you get them so late. Pick whichever you like and trade for the other one later.
Clefairy spawns at 1% on B1F and 6% on B2F. Stick to the deeper floor for better odds. They're level 8-12 and know Sing, which can put your Pokemon to sleep. Weaken them carefully since Metronome can randomly KO itself or your Pokemon. Great Balls from the Cerulean Mart work fine at this level range.
Depends on what you're after. Repels block encounters below your lead Pokemon's level, so a level 20 lead in Rock Tunnel filters out the common level 15-16 Zubat while still triggering rarer spawns. If you're grinding, skip them. If you're just passing through, they save time and healing items.
Only Rock Tunnel is completely dark without Flash. Every other cave in FRLG is fully lit by default. Flash itself comes from Oak's aide on Route 2, and you only need 10 Pokedex entries to claim it.
Escape Rope warps you to the last entrance you used and costs 550 at most Poke Marts. The move Dig does the same thing for free if a Pokemon on your team knows it. Both work in any cave or dungeon in the game.