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"Forgotten Challenge" is an instrumental piece composed by Yoko Shimomura. It was first featured in Kingdom Hearts Chain of Memories.
Kingdom Hearts Chain of Memories/Kingdom Hearts Re:Chain of Memories
Battle theme for Castle Oblivion.
Kingdom Hearts Re:coded
"Forgotten Challenge" is approximately two minutes and twenty-nine seconds long and plays at a tempo of 160 beats per minute and has a time signature of 4/4 time. The piece lacks an introduction and conclusion, allowing for smooth transitions between loops. The instrumentation is composed of: organ, harp, strings, timpani, cymbals, choir, and low brass instruments.