what is that triangular thing in the top left corner?

I suspect the one on the right is the key card, which I've already obtained. Now, I don't know what the triangle in the top left corner is.

Does anyone know?

I have the same question

so uh, iirc you need a keycard so you can access the lift that will take you to another place with a big round thingy, to process even further, you must have a cognitor mask so you can interact with the round thingy and you will get another ending. cmiiw