This seems pretty OP to me. Particularly because it can stack to 3. That would be a potential -6 | -6 to ALL enemy creatures for the rest of the game with the upped version. It essentially wipes out their ability to use just about anything short of a dragon (and even most of those are gone come to think of it) for the rest of the game. Since PC is not currently accessible enough to all elements this could cripple entire elements right now. (time, water, light, death, air, and especially life would be flattened due to lack of counters). This is just way too powerful in my opinion.
Take away the stacking (like nightfall and eclipse) though and I think it would be just fine.
To keep the stackability, you could maybe add a small damage to owner every round and have only that stack. Just my 2
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On a positive note, the theme is pretty cool and I really love the artwork.