Shrunken goblin skull earring
 

is currently usable at level 1, should only be clickable at level 15.

"Well ... it dosent raise your atk 30 .. more like 7-10 ... and you are correct it does not work at level 12 ... I am unsure what level it will start but I am guessing about the same level SK's get the spell ...
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"According to Lucy (which is a pretty reliable site), these start to work at level 15 at which point they give you +10 ATK.
"

Allakhazam says level 15 too

Never worked on Blue for me before 15.

currently working on my level 1 on red

Fixed, pending update.