I came up with this idea trying to create another Vitenka-style rule-breaking card for My Universe, My Rules for Challenge # 100. I have a feeling it's not quite whimsical enough for that, but it's a pretty interesting and rule-stretching card. It's like the black version of Yet Another Aether Vortex.

Played at the Bring Your Own draft, it became clear this shouldn't really be symmetrical.

Entertainingly, this is almost exactly half of Over My Dead Bodies.

I suppose, in theory, you could just make this an Unearth variant that you can only activate during your opponent's turns. But what's the fun in that?

Though, I'm a bit surprised I haven't seen a variant of this in a graveyard themed set:

Family Plot
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Enchantment
Exile a creature in your graveyared, : Target unblocked attacking creature becomes blocked.

Exiling creatures in graveyards as a cost seems like a good choice for combined flavor and mechanical reasons. You could probably make a religion cycle out of this.