This is a hack of the JP version of Megaman 2 called Rockman 2 - Dr. Wily no Nazo. The hack changes the weapons, boss behavior & palette, and level design.

• Rockman 2 - Dr. Wily no Nazo (J) [!].nes - GOODNES 3.14
• CRC32: 30B91650
• MD5: 055FB8DC626FB1FBADC0A193010A3E3F
• SHA-1: FB51875D1FF4B0DEEE97E967E6434FF514F3C2F2
• SHA-256: DEB88223311ACA8CA566B99D4063CA29D389D939FEE455F83AFAEC97C6F0A5D1