Half-Life: Alyx Walkthrough - Chapter 4: Superweapon (Part 4 of 11) - IGN

The crew finds out that the Combine are hiding something in the giant vault floating in the sky.
The crew finds out that the Combine are hiding something in the giant vault floating in the sky.

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Walkthrough part 4 - Half-Life 2: Episode 1 Guide - IGN

Half-Life: Alyx Walkthrough - Chapter 4: Superweapon (Part 4 of 11) - IGN

Walkthrough part 4 - Half-Life 2: Episode 1 Guide - IGN

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Half-Life: Alyx Walkthrough - Chapter 4: Superweapon (Part 4 of 11)