Just a simple guide on how to obtain the Yippee!! achievement.
The Yippee!! Achievement Guide
Very early in the cave system you’ll get to this ledge with the rope leading deeper in the cave, simply go over the rock bridge
Once you’ve crossed over the bridge, passing the rope leading down you’ll see some stalagmites. walk towards the left where they are, careful not to get stuck in them.
You will find a small cube with the “YIPPEE!” meme pictured on it, carefully go near it and pick it up.
Picture of the exact location of the cube.
Now you should have unlocked it!
Thank you for reading, hope this helped you get the achievement, have a good day!