First of all, i think that it would be more logical for it to be just one skull(centered) when the block is placed on the ground.The default texture just looks weird imo. It could also be nice for building if the skull could be rotated to face different directions(This tweak could be useful for carved pumpkins as well).The third tweak that i want to suggest is to be able to craft the skull block into different states with up to 8 skulls, whereas more skull you add, the more there will be on the block, but they can be stacked realistically, not on top of one another, but just randomly.
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