Unlock the following costumes by performing the corresponding tasks:

COSTUME - HOW TO UNLOCK
Barbarian - Collect all Stamina Campaign signs.
Earthquake - Find the secret item in Port Alex.
Fire - Find the secret item in Port Alex.
Frog - Beat the Lahar rescue in Stage 15 in under 25 seconds.
Heavy Rain - Beat the game.
Hurricane T-shirt - In Stage 18 - "Mud And Mercenaries", examine the door to the female toilets multiple times.
Mech Ray - Beat Real Disaster mode.
Rescuer Uniform - Beat all 45 rescues.
Samurai - Collect all 100 titles.
Tsunami - Find the secret item on the ferry.
Volcano T-shirt - Save Iris from the molten lava, then jump across the gap to find the shirt in a barrel.