So far, only one person has asked about this one, but I had found this interesting before anyway. I nearly put these with the original post. I double checked and wrote up my notes so they’re (hopefully) understandable.

This is a possible way to get the reference lines, but there may be a simpler way. I want to point that out because this model strikes me as having lines in more random places than most crease patterns. That is, it seems more like a model that has steps like in diagramed models. Creases found based on previous steps would be much easier to fold/follow. However, it may just have intentionally difficult to find reference lines for the challenge part.

My finished model (from the double checking) follows the reference line diagrams below.

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