>>10583132Here is the set. It was from LEGO Dimensions. I picked it up ages ago on a whim when the game was still running. Actually got me into Portal in general. I found the Cube piece looks better if you take all the extra bits off and just stick the cube itself on the toy tag. It was the only deadweight piece in the whole game to solve some of the puzzles. I also ordered another six tiles and made on my own using that trick with a pair off the five-sided 1x1 pieces.
>>10583053My thanks anon. I've been curious about that for ages. It feels good to have the answer.