Aspè, forse ho trovato:
When you complete the game and save, if you load up that save you'll start
again with your health and grip intact. You can also replay any of the
Colossi from inside the temple by going up to the respective statue and
preying (Circle button). By doing so you can unlock various items. This also
occurs in Hard mode, where the times are slightly different, as are the
rewards.
Devi ricaricare il tuo precedente save, non iniziare una nuova partita.
In poche parole il time attack si attiva solo in Reminescence Mode.