Super Mario RPG: Legend of the Seven Stars/Hidden Treasure Boxes

The first time you go to Mushroom Kingdom at the beginning of the game, Toad will meet you at the entrance to the castle and you need to jump on his head and then jump on top of the doorway to reach this hidden treasure chest. This is one of the hardest chest to get because this is the only time you will have the extra step (Toad's head) to jump high enough to reach it.