How can I dig to 256 floor?

Well, the fastest thing to make Karen like you is to give her a wrapped present every day(give her lots of wine, or berries but mostly wine).

#2 Go to the water fall by the hotspring and throw a flower into the lake, for the first 5 days she'll give you a power barry, and then for the 10 days you've been there, she'll ask you who you like and give her a name and that girl will like you more, and #3, eat alot of power berries to get your stamina level higher and you'll eb able to last longer in there, also, when you find a black grass, store it in your rucksack and when you get tired, eat 1 or 2 and you'll be good for a few minutes (get a big rucksack so you'll be able to store lots of black grass).

First you must get few Torbojolt and Bodogizer, you must also bring a basket. Go in and save your game and start searching, after you found the ladder, load your game and go to the exact place where you found the ladder, because the ladder will stay in exact place.

Go in the ladder and save again. Do this method until you reach the 255th floors. Beside that you can found power berry behind the winter mine, also you can found cursed tool in winter mine in floor 69, 79, 39, 59, 29 and 49. You can also found pink diamond and sell it for 10,000, you can find it in floor 30, 70, 90, 110, 130, 170, 190 and 255, you can get 38 (8 in your rucksack and 30 in your basket) so in the next day you can get 380,000 !!!

And you can get the town cottage easily. This is the best place!!!