Thinking of:
After Ash lost to Tobias in Sinnoh Leauge Victors, the night before he went back to Kanto, he heard the Pigmask theme, he went outside to see what it was (Around 3 AM in Sinnoh Time), and he was caught by Pigmasks. They made a clone of him, except more immature, and was supposed to think he was 10. The real Ash had his mind taken, and replaced as if a bot of Porky's.
Somehow, Misty got an ocarina, and was really hold, and so was you, but on Mt. Tajiri, The Masked Man 2 (Ash) was about to kill everyone, and to get his original memory back, you, and Ninten, Ana, Loid, Ness, Misty, and you have to do or sing the 8 melodies.