Nope its not for finding a secret land. You can use that to remove the big boulder. You
know the one behind the waterfall? Yup that. Then there is a little cave there where there
is a plot of land for you to farm.

haha my bad, but thank you^^

where to get sword?

you can get the legendary sword from the 255th floor of the second mine. In order to get
it on DS Cute, you must have all of your tools (including the fishing rod) upgraded to
Mythril. It's a waste of time to go down there if you don't have those tools upgraded.
Just kill all of the animals on the floor (you don't have to clear it entirely but there
are some good gems there) and a boulder will disappear on the top wall. Walk through and
pick up the sword. When you exit the mine, equip the sword, walk to the boulder by the
waterfall and press A, NOT X as usual for tools. This cool martial-arts style sequence
then comes on, et voila!!

wait on ds cute, how do you get to the mine, i cant find it!