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New Pokémon Available

Red	Blue	Yellow
Machop Onix		Onix

Rock Tunnel is the only avenue between Route #10 and Lavender Town. Unlike the caverns beneath Mt. Moon, Rock Tunnel is pitch black, and you must rely on the Flash technique (HM 05) to light your way. Use the labeled maps to follow the ladders through the tunnel to the exit. The tunnel has two levels, but there really is only one main path.

1	Pokémaniac	1150
	Cubone	LV23
	Slowpoke	LV23
2	Hiker	665
	Geodude	LV19
	Machop	LV19
	Geodude	LV19
	Geodude	LV19
3	Hiker	700
	Onix	LV20
	Onix	LV20
4	Hiker	735
	Geodude	LV21
	Graveler	LV21
5	Jr. Trainer♀	440
	Bellsprout	LV22
	Clefairy	LV22
6	Jr. Trainer♀	380
	Pidgey	LV19
	Rattata	LV19
	Rattata	LV19
	Bellsprout	LV19
7	Jr. Trainer♀	400
	Meowth	LV20
	Oddish	LV20
	Pidgey	LV20

Rock Tunnel encounters

Zubat	50%	50%	50%
Geodude	26%	26%	26%
Machop	16%	16%	16%
Onix	8%	8%	8%

[edit] Into the dark

The wild Pokémon in Rock Tunnel seem to attack more often than their above-ground cousins, and if you're being attacked every few steps, it may take you awhile to reach medical attention. For that reason, it's a good idea to bring either a Pokémon that knows Dig, or plenty of Escape Ropes just in case you need to make a quick getaway. If you don't have either of those, this would be a good time to try the Repel potion, which keeps minor Pokémon at bay.

You'll have a much tougher time, however, avoiding the many trainers lurking in the shadows. You'll have to use Flash if you want to see where you're going in here. It's possible to proceed without it, but you'll probably want the light so you can avoid some of this area's tedious, difficult trainer encounters. If you want to avoid a duel, walk a path that's far away from the trainer or that's out of the trainer's line of sight.

1	Pokémaniac	1250
	Slowpoke	LV25
2	Jr. Trainer♀	440
	Oddish	LV22
	Bulbasaur	LV22
3	Pokémaniac	700
	Charmander	LV22
	Cubone	LV22
4	Hiker	875
	Geodude	LV25
5	Hiker	700
	Machop	LV20
	Onyx	LV20
6	Jr. Trainer♀	420
	Jigglypuff	LV21
	Pidgey	LV21
	Meowth	LV21
7	Hiker	735
	Geodude	LV21
	Geodude	LV21
	Graveler	LV21
8	Pokémaniac	1000
	Slowpoke	LV20
	Slowpoke	LV20
	Slowpoke	LV20

#66 Machop	#95 Onix
They're not a common sight in any version, but anyone can track down and capture a Machop with a bit of effort. Machops are strong on offense and HP and only get stronger as they evolve: Into Machoke at level 26, and then into Machamp once they're traded.	Onix is a fair Rock-type Pokémon to have. They have exceptional Defense and decent Speed, but rather poor HP, Offense, and Special Defense, making it rather susceptible to Water attacks. It learns Rage at level 25 which can be a useful Normal-type move when you have no other options.