There are also a number of secrets in the game. Different hidden treasures, such as coins and golden shapes, which increase the player's score, as well as "lives", etc. can be found by interacting with the game's environments. The bonus-life system departs from the previous games, where life is gained by saving hostages; the loss of these events are substituted with an increase of extra-life pickups in the environment. There are also "treasure rooms" that can be accessed using different techniques (such as shooting a certain spot or throwing a grenade in a certain area), which contain multiple items that can be obtained at once within a limited time.