This idea again. The HP limit works, except you're only bounding how much the different scaling of attack and health can be exploited
I'll quote myself: I think the issue is that attack scales linearly, whereas health scales with diminishing returns. Having the swap apply something similar to how Catapult scales might make a health/attack swap card be balanced even in the face of Titan
If the resulting attack is half that of catapult: Titan becomes 17|8, Ruby Dragon becomes 1|17
If the resulting health is doubled to maintain inverse reversing itself: Titan becomes 17|16, Ruby Dragon becomes 1|34
If rounding is applied reversal will result in 9|50 on Titan, 15|2 on Ruby Dragon
http://elementscommunity.org/wiki/CatapultFor attack: Find the creature's health in the table's Health column. Take Damage, halved
For health: Find the creature's attack in the table's Damage column. Take Health, doubled