The Dark Cave is located in Johto. You need TM70 Flash, HM04 Strength and HM06 Rock Smash to get through this cave.
Items
Generation II
BlackGlasses G/S/C
Dire Hit G/S/C/HG/SS
Full Heal G/S/C/HG/SS
Hyper Potion G/S/C/HG/SS
Potion G/S/C
Revive G/S/C
Black Flute HG/SS
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