Mega Man II/Rockman World II is notorious as the black sheep of the Game Boy Mega Man games for many reasons. Perhaps the most glaring of these is its peculiar soundtrack, which is bizarrely high-pitched, off-key, and extremely grating compared to pretty much any other Game Boy game, let alone the rest of the series.

This hack attempts to improve the music by fixing two apparent errors:

1. The first is an objective programming mistake: the game’s note-to-frequency conversion table is wrong. Some values are correct while others are one higher than they should be, resulting in over a quarter of the notes playing off-key.

2. The more obvious problem, and the more subjective one, is that much of the music has the lead instruments set an octave higher than most people find pleasant.

Problem 1 is a simple fix: the frequency table has been regenerated with the correct values, fixing the out-of-tune notes.

Problem 2 has been handled, in most cases, by lowering the two square channels (used for leads) one octave and leaving the wavetable channel (used for bass) untouched. A few tracks have been handled specially; see the readme for details.

Note that the sound effects are unchanged, as they’re stored in a different format that directly specifies the intended frequencies instead of doing a note-to-frequency conversion.

Included in the download are three IPS files, one for each of the game’s regional variants (Japan, USA, and Europe).

• ===Japanese Version===
• No-Intro filename: Rockman World 2 (Japan).gb
• CRC32: C34D265E
• MD5: C05B47DF8BDFE770BE228E51BC42DA84
• SHA-1: 5D35BAA2FADD07796ED8B441F82ED5B136A999C7
• ===USA Version===
• No-Intro filename: Mega Man II (USA).gb
• CRC32: E496F686
• MD5: 7FE07271D04ED9E0BC0663DDE55A2AE4
• SHA-1: 334F1A93346D55E1BE2967F0AF952E37AA52FCA7
• ===European Version===
• No-Intro filename: Mega Man II (Europe).gb
• CRC32: 5E90CB48
• MD5: B9CFEE05797BEB8FF7E259EE77EAF2FB
• SHA-1: D19993A4630E7F9450FF6469115F4095F6F29667