The Portal games are not only two of Valve’s most iconic games, but two of the greatest puzzle games ever created. Players create two portals they can travel between to reach unobtainable areas, build up momentum, and a plethora of other ingenious uses to solve each test chamber. Portal Reloaded, a fan-made mod for Portal 2, was released on April 19 of 2021, 10 years after the game was originally published. This highly anticipated mod introduces a third portal that allows players to pass through the present and future, and just like the main games, has plenty of its own secrets to find.

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One of the secrets players can stumble across in Portal Reloaded are companion cubes hidden throughout the test chambers. These cubes served as puzzle companions in the first game and have made a reappearance in this mod as an Easter egg. Here’s a look at where two of the hardest ones to find are, as well as tips on how to find other ones.

Finding Hidden Companion Cubes in Portal Reloaded

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Portal Reloaded has a total of 25 test chambers filled with complex mind-bending puzzles to solve. To find one of the many hidden companion cubes, players will need to complete test chamber 17. If the giant number 17 displayed in the test room isn’t a good enough indicator, this puzzle involves launching a cube in the air with an aerial faith plate, which is the name for Aperture Science’s patented launch pad. Now, to find the pink-hearted companion cube in this area, test subjects won’t need to go out of their way.

After completing the puzzle, the player will need to use an aerial faith plate to propel themselves through the air and onto a platform on the other side. During this glide, the player will be launched through an abandoned testing room suspended in the air where the cube is hidden. Turn the camera to the left to see the easter egg nestled in the corner. This is one of many hidden companion cubes scattered throughout the mod like ‘hidden Mickey’s” from Disneyland. To find more, look in every nook and cranny of the dilapidated test chambers by zooming in with the mouse’s middle button.

The most difficult companion cube to find can be located shortly after solving the 21st test chamber, which involves light bridges. The test chamber announcer will open a room on the right with two turrets that fire at the player, but they’re quickly disposed of by using portal shenanigans. The linear pathway suggests the player should move on, but they’ll miss out on the hidden companion cube if they do.

Shoot one portal into the same room as the two turrets, whether it’s on the wall or floor does not matter, and then shoot another one at the white wall at the end of the path. This wall is meant to be used as a portal surface to progress the game, but here it’s going to be used to access the secret. After passing through the portal, look up and to the left or right, varying depending on what direction the player entered, in the turret room to see the cube. It may seem unobtainable, like all the other secret ones up until now, but a crafty player can get within the cube’s grabbing range if they use their portals, or other materials at hand, cleverly.

Next: Will There Be A Portal 3?

Portal Reloaded, the mod for Portal 2, is available on PC.