If you're like everyone else and not some inhuman gaming freak that can beat any challenge anywhere, you probably think that 8-3 on the Japanese SMB2 is the hardest piece of sh*t in the game and most likely in the Mario series. But I've got a technique that got me through easily.
1.Run nonstop(may take practice) until you get to the wall in front of a Pirahna Plant. The timing of this nonstop run should get you past those two Hammer Bros.
2. Run and jump on the springboard and hit the nearest Koopa, then run and jump through the next two Hammer Bros.(make sure you don't run too far). Again, this timing should get you through.
3. Reveal the two hidden blocks at the end and run jump on them to make it to the balanced platforms.
4. Make the second one as high as it will go without stopping you from jumping, jump from it to the two blocks, and hit the flagpole(don't worry about the last Paratroopa).
I beat it three times in a row with this method, then I quit to post this. I did it on Mario All-Stars, so it may not be the right timing on SMBDX.
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Mario:Hey I''ve-a been working here for-a 20 years a-now, and I''m still a-getting paid 8 a-bucks an hour. What the f***''s up with that!?
Miyamoto:You get free board anyway. You don''t see Luigi or Wario complaining, now do you?
Mario:They a-just don''t care. Luigi justs spends a-it all on a-doin'' hookers, but a-now Wario might a-want more since he rediscovered-a the wonderful world of-a marijuana yesterday!
Miyamoto:Not again! He only managed to quit a year ago!