Thought I would test out the Dangerous Maraquan Yo-yo we got at the end of Daily Dare 2016 and discovered it was a defensive weapon, which is harder to test in 1P than I thought it would be.
First time I used it, it defended 2 fire icons, 2 water icons, and 2 earth icons.
Second time, it defended 4 fire icons, 2 water icons, and 2 earth icons.
Third time, it defended 4 fire icons only.
Fourth time, it defended 4 fire icons and 2 water icons. No earth icons were mentioned.
It would say different things each time such as "you fling your yo-yo to defend against the water attack" or "the physical attack" but I don't think that affected the number icons directly.
I realize now that I should have recorded more details of each battle and if anyone has a good guide to testing things (like what to write down), I'd be happy to follow it, but so far I can say it's multi-use, defends 2-4 fire icons, 2 water icons, and 0-2 earth icons.