Dungeon!
There is a large hole in the Ura Internet area 6 that is surrounded by purple slime on a platform and in order to reach the secret dungeon, you need to have these chips:
Bug Curse, Muramasa Blade, Black Wing, Element Dark and Poison Anubis.
Once you have those then when you get close to the hole, it will suck you down into the secret dungeon called Black Earth!!!
If you need more help, we've got more Mega Man Battle Network 4: Blue Moon cheats and also check out all of the answers for this game
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