Mario and finish the game once. You will get ranked according
to how you did and receive a letter grade. Save your game.
You now have the option to restart Luigi's two ways (in addition
to going to the completed Gallery). The first option lets
you go back to the regular Luigi's Mansion Mode. The second
option, called Ura-Yashiki (Another Mansion) in Japanese,
lets you restart the game -- and presumably some of the things
in the mansion have been changed around.
first one is located on the first floor, in the south-west
corner of the Mansion. After you have sucked in the candle-carrying
butler, exmaine the room with your Game Boy Horror to find
a mousehole. Press A to activate it and go inside to enter
the trasure room.
second treasure room is accessible from the roof top. Use
the elevator in the toy chamber to get on the roof, the go
all the way to the right and climb up on the chimney. Fall
down and you will land in another treasure room.
to the right side of the graveyard. just underneath the balcony
with toad. There is a seed. Once you can use water (BEFORE
the second boss) water the seed. enter the doghouse, and defeat
the second boss. return to seed and water again. continue
with game, but come back and water it after you fight the
3rd boss. It will bloom and produce a diamond!