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.
Massive dragon
2.
Basalt dragon
3.
Jade dragon
4.
Light dragon
5.
Obsidian dragon (with eclipse)
6. Growth creatures (eventually)
7. Improved mutants (sometimes)
8.
Anything with basilisk blood
9.
Flying Titan
10.
Armagio/Elite Armagio
With attack + hp >18 as our limit, we add the following:
1.
Ivory dragon (with eclipse)
2.
Colossal dragon
3.
Golden dragon
4.
Sky dragon
That leaves all the dragons from
and
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.