Start by Digging Ice in Antarctica and Dig Out Cthulhu

I am Li Yun, a linguist. I spent my life talking to unknown civilizations until we actually found it under the Antarctic ice. Thinking it was communication, we played a synthesized greeting into the abyss. We were wrong. That low-frequency "echo" is not a language at all, but a spiritual plague. Now, it's talking in my head. It showed me incomprehensible knowledge at the cost of my sanity. My teammates were either mad or became its puppets, muttering crazy ritualistic prayers. Carter, the leader, only cared about bullshit "knowledge" and Dr. Mark and I were the only ones trying to stay awake. But what can we stop? The entire outpost beneath our feet became a giant resonating chamber, and we were the lambs on the altar. Don't listen to this frequency... Because once it gets into your head, it never goes away