Do you really need the secret items on sonic adventures 2 battle, for example sonic's Power Up Magic Gloves and knuckles or tail's mystic melody or other secret things too complete the game?
Yes, thoes Level-Up items are needed to complete the game. Mystic Melody is used for clearing most "Find the lost Chao!" missions, Magic Hands/Gloves on the other hand are not really nessisary to finish the game, but they do make enemies much more easy to distroy.