That said, it'd a lot more balanced if it was sum, and the upped went to ~18, the unupped probably 20. Wouldn't have much effect except on strong creatures, namely dragons.
Assuming we use a sum of attack + hp >20 as our limit, which creatures would be affected?
1.
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Massive dragon
2.
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Basalt dragon
3.
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Jade dragon
4.
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Light dragon
5.
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Obsidian dragon (with eclipse)
6. Growth creatures (eventually)
7. Improved mutants (sometimes)
8.
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Anything with basilisk blood
9.
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Flying Titan
10.
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Armagio/Elite Armagio
With attack + hp >18 as our limit, we add the following:
1.
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Ivory dragon (with eclipse)
2.
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Colossal dragon
3.
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Golden dragon
4.
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Sky dragon
That leaves all the dragons from
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and
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totally unaffected. And of these 5 elements, the only creatures to be affected would be end-game scarabs (because of their swarm ability.) That's why I used multiplication instead of addition since you get a lot more breadth (and a little more depth) of potentially affected cards.
In the end, the difference between the original multiplication-scheme and the suggested sum-scheme: losing coverage of 7 upped creatures and 10 dragons.
Neither version would impact some of the most popular cards including FFQ, pharoah, vampire, arctic octopus,
anubis, physalia and RoL.