Defeating the White Witch
On the last level you will fight the White Witch.To defeat her, run until she does a backflip. Then, above her head a circle will read "5+". Hit her five times then a bow and arrow will appear. Shoot her with Susan. Then, hit her with Edmund. She will call giant ogres to attack you. Kill them with the barrels. Repeat, then set the barrels on fire and hit her with them Repeat the first process, repeat again, then Susan can blow the Ivory Horn to summon Aslan, the king of Narnia. After that, the level will be over.
Full warmth
When entering a new area or screen, save the game then restart. You will start with full warmth.
Water mill
After the beaver chews through the wood up on the hill, you will reach a location with a water mill looking object. Use Edmund or Susanna and throw Lucy at the ice blocks below the cliff.
Bonus levels
Reach the indicated game completion percentage to unlock the corresponding bonus level.
To Western Wood: 24%
Allies Enclave: 36%
Frozen Lake: 48%
The Great River: 62%
Follow Aslan: 78%
The Witch's Castle: 97%
Movies
Reach the indicated game completion percentage to unlock the corresponding movie.
Peter Recording Session: 3%
Susan Recording Session: 6%
Edmund Recording Session: 12%
Lucy Recording Session: 16%
The Making of Narnia: 30%
Story Boards: 42%
Prototype Battlemarch Demo: 54%
From Concept to Game: 69%
Concept Art Blend Tests: 89%
Unused Models: 100%