Tomb Raider: Underworld
Successfully complete the game on any difficulty to unlock the white swimsuit for use in the Mediterranean Sea Expedition.
Successfully complete the game on any difficulty to unlock Treasure Hunt mode, which allows the game to be replayed without the puzzle completion requirements in order to collect any treasure missed in your previous playthrough.
Successfully complete the indicated task to unlock the corresponding concept art at the "Extras" menu:
- Creature Concepts: Collect all treasures.
- Environment Concept Art for Arctic Sea and Amelia Concepts: Successfully complete Arctic Sea Expedition.
- Environment Concept Art for Coastal Thailand and Alister Concepts: Successfully complete Coastal Thailand Expedition.
- Environment Concept Art for Croft Manor and Doppelganger Concepts: Successfully complete Croft Manor Expedition.
- Environment Concept Art for Med Sea and Amanda Concepts: Successfully complete Mediterranean Sea Expedition.
- Environment Concept Art for Mexico and All Men Concepts: Successfully complete Southern Mexico Expedition.
- Environment Concept Art for Ship and Natla Concepts: Successfully complete Andaman Sea Expedition.
- Environment Concept Art for Jan Mayen Island, Gear, and Artifacts Concepts: Successfully complete Jan Mayen Island Expedition.
- Game Flow Storyboards: Successfully complete the game on the Master Survivalist difficulty.
- Lara Concepts: Collect all six Relics.
- Zip and Winston Concepts: Successfully complete the Prologue.
- Environment Concept Art for Arctic Sea and Amelia Concepts: Successfully complete Arctic Sea Expedition.
The hidden Relics can be found at the following locations:
Mediterranean Sea Expedition
Coastal Thailand Expedition
Croft Manor Expedition
Southern Mexico Expedition
Jan Mayan Island Expedition
Arctic Sea Expedition
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