Easter egg under Mystery Lake map railway bridge?

[EternityTide]

I'm currently playing the Mystery Lake map, and am thoroughly enjoying the new features and tunings.

I just took shelter in a Fluffy-less Carter Hydro Dam, and on my departure the next morning, I ventured down onto the river bed, where I found, nestled under the bridge supports in some kind of crude shelter of ice blocks, a burnt out campfire. One which I did not make.

Not sure whether to be pleased or afraid.

[brenton_nichol]

I saw that too, and was also puzzled. But in a later playthrough, I revisited the location and discovered that a certain item very occasionally will spawn there next to it

[EternityTide]

a certain item.... a rifle?