Walkthrough
In order to gain access to the Cinnabar Island Gym, you will need to find the key to the building within the Pokemon Mansion found on the island. The Pokemon Mansion is a very large building full of both Wild Pokemon and Pokemon Trainers. In order to find the Secret Gym Key, you will need to use the statues found throughout the Pokemon Mansion to earn access to certain rooms.
Wild Pokemon
1st Floor:
Raticate (30%): Levels 32-36
Koffing(FireRed)/Grimer(LeafGreen) (30%): Levels 28-30
Rattata (15%): Levels 26-28
Growlithe(FireRed)/Vulpix(LeafGreen) (15%): Levels 30-32
Grimer(FireRed)/Koffing(LeafGreen) (5%): Level 28
Weezing(FireRed)/Muk(LeafGreen) (5%): Level 32
2nd Floor:
Raticate (30%): Levels 32-36
Koffing(FireRed)/Grimer(LeafGreen) (30%): Levels 28-30
Rattata (15%): Levels 26-28
Growlithe(FireRed)/Vulpix(LeafGreen) (15%): Levels 30-32
Grimer(FireRed)/Koffing(LeafGreen) (5%): Level 28
Weezing(FireRed)/Muk(LeafGreen) (5%): Level 32
3rd Floor:
Raticate (30%): Levels 32-36
Koffing(FireRed)/Grimer(LeafGreen) (30%): Levels 28-30
Rattata (15%): Levels 26-28
Growlithe(FireRed)/Vulpix(LeafGreen) (15%): Levels 30-32
Grimer(FireRed)/Koffing(LeafGreen) (5%): Level 28
Weezing(FireRed)/Muk(LeafGreen) (5%): Level 32
Basement Floor 1:
Raticate (30%): Levels 34-38
Koffing(FireRed)/Grimer(LeafGreen) (30%): Levels 28-30
Growlithe(FireRed)/Vulpix(LeafGreen) (15%): Levels 30-32
Ditto (10%): Level 30
Grimer(FireRed)/Koffing(LeafGreen) (5%): Level 28
Rattata (5%): Level 26
Weezing(FireRed)/Muk(LeafGreen) (5%): Level 34
Pokemon Trainers
1st Floor:
Youngster Johnson: Level 33 Ekans, Level 33 Ekans, Level 34 Raticate
Scientist Ted: Level 29 Electrode, Level 29 Weezing
2nd Floor:
Burglar Arnie: Level 34 Charmander, Level 34 Charmeleon
3rd Floor:
Burglar Simon: Level 38 Ninetales
Scientist Braydon: Level 33 Magnemite, Level 33 Magneton, Level 33 Voltorb
4th Floor:
Burglar Lewis: Level 34 Growlithe, Level 34 Ponyta
Scientist Ivan: Level 34 Magnemite, Level 34 Electrode
Items
1st Floor:
Escape Rope: On Ground
Protein: On Ground
Carbos: On Ground
Moon Stone: On Ground
2nd Floor:
Zinc: On Ground
Calcium: On Ground
HP Up: On Ground
3rd Floor:
Max Potion: On Ground
Iron: On Ground
Rare Candy: ItemFinder
Basement Floor 1:
Full Restore: On Ground
TM14: On Ground
TM22: On Ground
Secret Key: On Ground
Elixir: ItemFinder