Original Tempest
Get a #1 highscore enter your initials as "H V S" or "YIFF!". Tempest 2000 and Tempest Plus should appear on the main menu as options.
Melting Mode + Level Skip
Hold L1 + R1 + Up-Left + Triangle + Circle + Start + Select. To confirm the entry , a grinding noise should play. Release and then hold L2 + R1 + X + Triangle + Down. A voice will confirm the code was entered properly
Now that you've enabled the Melting Mode, all you have to do skip levels is press L1 + L2 + R1 + R2.