Please help me finding this item (Cobweb Cocoon)

I recently got into Haypi Monster 3, and have been enjoying the game so far. One of my favorite monsters is Octomom; its combination of unique skills and traits make it useful both as a support and a DPS, and being a rare it takes minimal investment. However, while I would like to evolve my Octomom into a Octola for the extra stats and access to new abilities, I cannot find the evolution item, the cobweb cocoon. I initially assumed it would be in the rotating honor shops on the battlefield, but after what must have been hours of searching I never saw it once. Is it just rare, or is it somewhere else? In game, it just says “unknown location,” which isn’t very helpful. I know this forum isn’t very active, but I’m reaching out because I figure that SURELY someone more experienced in this game has seen one somewhere before and remembers where to find it. If you can help, it would be greatly appreciated. Thank you!