Cerulean Cave Pokémon Yellow · Dungeon

Map of Cerulean Cave in Pokémon Yellow — 1F (Game Boy map)

Cerulean Cave is a post-game dungeon in Cerulean City, open only after you become Champion. It is full of high-level wild Pokémon and rare items. Mewtwo waits at the far end of B1F.

Wild Pokémon: 14
Items: 15
Trainers: 0
Needs: Surf

Connects to: Cerulean City

Where Cerulean Cave is on the Kanto town map Position on the Kanto town map

Gift and special Pokémon

Mewtwo Lv. 70

Mewtwo waits at the far end of B1F. It is only open after you become Champion.

Wild Pokémon

1F

Walking in the cave encounter rate 10/255 per step
Pokémon	Type	Lv.	Chance
Golbat	PoisonFlying	50–55	39.8%
Graveler	RockGround	45	15.2%
Sandslash	Ground	52	9.8%
Gloom	GrassPoison	55	9.8%
Weepinbell	GrassPoison	55	9.8%
Ditto	Normal	55–60	5.5%
Parasect	BugGrass	54	5.1%
Venomoth	BugPoison	54	5.1%

Fishing
Rod	Pokémon	Lv.	Chance
Old Rod	Magikarp	5	100%
Good Rod	Goldeen	10	50%
Good Rod	Poliwag	10	50%
Super Rod	Seaking	35–55	60.2%
Super Rod	Goldeen	25	39.8%

2F

Walking in the cave encounter rate 15/255 per step
Pokémon	Type	Lv.	Chance
Golbat	PoisonFlying	52–57	39.8%
Graveler	RockGround	50	15.2%
Sandslash	Ground	56	9.8%
Rhyhorn	GroundRock	50	9.8%
Ditto	Normal	60	9.8%
Rhydon	GroundRock	58–60	5.5%
Gloom	GrassPoison	58	5.1%
Weepinbell	GrassPoison	58	5.1%

B1F

Walking in the cave encounter rate 25/255 per step
Pokémon	Type	Lv.	Chance
Golbat	PoisonFlying	54–59	39.8%
Graveler	RockGround	55	15.2%
Ditto	Normal	60–65	14.8%
Rhyhorn	GroundRock	52	9.8%
Rhydon	GroundRock	62	9.8%
Lickitung	Normal	50–55	5.5%
Chansey	Normal	56	5.1%

Fishing
Rod	Pokémon	Lv.	Chance
Old Rod	Magikarp	5	100%
Good Rod	Goldeen	10	50%
Good Rod	Poliwag	10	50%
Super Rod	Seaking	40–60	60.2%
Super Rod	Goldeen	30	39.8%

Grass, cave and surfing chances are the Generation I encounter slots (10 slots weighted 51, 51, 39, 25, 25, 25, 13, 13, 11 and 3 out of 256); the Super Rod picks from four slots weighted 102, 76, 51 and 27, the Good Rod is 50/50 and the Old Rod always hooks a level 5 Magikarp. Where to find every Pokémon.

Items

Item	How	Where
Rare Candy	Item ball	1F
Max Elixer	Item ball	1F
Max Revive	Item ball	1F
Ultra Ball	Item ball	1F
PP Up	Hidden	1F
Rare Candy	Item ball	2F
Ultra Ball	Item ball	2F
Max Revive	Item ball	2F
Full Restore	Item ball	2F
PP Up	Hidden	2F
Ultra Ball	Item ball	B1F
Ultra Ball	Item ball	B1F
Max Revive	Item ball	B1F
Max Elixer	Item ball	B1F
PP Up	Hidden	B1F

Hidden items need the Itemfinder or a lucky press of A on the right tile.

Tips

Mewtwo is level 70; use the Master Ball from Silph Co. if you still have it.
Ditto, Rhydon and Chansey are available in the cave, plus many Ultra Balls and Max Revives.
Surf is required to cross the water on B1F.
Stock up on Full Restores, Max Revives and Ultra Balls.
Save before the Mewtwo battle.

Walkthrough: Part 13: Victory Road, Elite Four and Champion

More maps

FAQ

When can I enter Cerulean Cave in Pokémon Yellow?

Only after beating the Elite Four and becoming Champion.

Where is Mewtwo?

At the far end of B1F in Cerulean Cave.

What level is Mewtwo?

Level 70.

What Pokémon can you catch in Cerulean Cave in Pokémon Yellow?

14 species: Golbat, Graveler, Sandslash, Gloom, Weepinbell, Ditto, Parasect, Venomoth, Seaking, Goldeen, Rhyhorn, Rhydon, Lickitung, Chansey. The tables show levels and encounter chances from the game data.

What items are in Cerulean Cave?

15, including Rare Candy, Max Elixer, Max Revive, Ultra Ball, PP Up, Full Restore.

Sources & picture credits

Guide text is original retrogameindex writing, checked against Bulbapedia and the game data. Wild Pokémon, encounter rates, items, trainers, gifts and shops come from the pret/pokeyellow decompilation of the English game (pret/pokeyellow e89ead154b). Maps and sprites © Nintendo / Creatures / GAME FREAK, archived from the Bulbagarden Archives (listed on the image gallery).