Hints
To do a small jump, hold Shift and press Alt + Up and Left and Right.
To do a back-flip, go to the side of a ledge/block, hold Shift and Down, then press Ctrl. She will then do a back flip down the ledge.
To dive, go to the side of a ledge near water and press Ctrl. To take a big, looong jump, hold Up and Sprint, then press Alt.
We have more cheats and tips for this game here, Tomb Raider: The Angel of Darkness cheats
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