Simply add a 1x1pixel black square to the parts that you don't want. There is a skull with a top hat, a doll's head, a cube or dice, and a parrot or bird head ... many possibilities, for example; if you use my opacity on the skull, you can put the hat on the doll head.

Maps

Doll head:
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Skull:
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Parrot:
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Dice:
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Hat opacity:
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