Tomb Raider I-III Remastered Starring Lara Croft

In the beginning of Unfinished Business, after sliding down where the main game ended, walk further and lower yourself in the first gap ahead, you follow the route until there's another gap with a boulder ahead waiting for you to be triggered. After triggering you jump over the gap and follow the route until you come in a fleshy chamber with a hole in front of you.

Walk to the hole which appears to be a lava pit and stand at the corner, facing a triangle shaped opening. In that opening lies a small medi-pack. You can easily jump from the corner, over the pit, into the triangle shaped opening, if you're aiming for the widest part. Grap the medi-pack and the achievement should pop shortly after that.

I've made a clip to make it easier: https://xboxreplay.net/gameclip/lid-9000003d5ae96-a84e0f66fb...

And a screenshot of the hidden medi-pack: https://gamerdvr.com/gamer/luke-hermans/screenshot/29663845

Tomb Raider 1 Unfinished Business - Atlantean Stronghold (Level 1)

From the start of the level, safely drop through the hole in front of you and then run down the hallway to wait for the boulder to fall into the lava pit. Continue forward and use a swan dive (hold Walk button while performing a forward jump) from the corner to land inside the angled alcove for the medipack.

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