Lack of cards has never been the biggest issue. If we only add cards, those cards will be available to rainbow player as well.
Lets say we add 10 cards to each element. The mono-player gets 10 more cards to choose from while rainbow player gets 120. See what I'm saying?
However a numerical advantage means less and less as the numbers involved get higher and higher. Jmizzle agrees with me on this point and his explanation is sufficient so I'll simply leave you with that.
My argument is that as more and more cards are added, card space in a rainbow deck becomes much, much more valuable. There are some really, really good cards available now like Aflatoxin, Antimatter, and Rage Potion, but there just isn't enough space in a rainbow deck for them. As more and more cards are added, rainbow decks will definitely improve, but not at the same pace non-rainbows will, because there will be too many cards to use in a single deck effectively. Gotta love the law of diminishing returns...
Otyugh is a good example of this. It's a relatively cheap with and an insane ability. One Otyugh can easily be the difference between life and death. Now if I play mono-gravity, Otyugh isn't that overpowered because I'm lacking the synergy with Rain of Fire, Heavy Armor, etc. But when I play rainbow, I can cherry-pick all the best cheap cards making my deck much stronger than mono-decks.
You're touching upon exactly what I was saying only you're looking at it in a different way. It's not that some crazy Rainbow Magic makes Otyugh better. It's just that Rainbow has access to cards that work well with Otyugh while Gravity lacks its own equivalents. Now what I am saying is rather then lament at how Rainbow can use these cards and seek to take it away from them why not wait until Gravity has this luxury too?
Every Element seems to be set on a path to gain access to its own take on each simple concept like Healing, Damage, Creature control etc. Not every Element has yet gained all of these things. And Gravity should, if it is designed properly gain much better synergy with itself then Rainbow can have with outside cards. Look further down the line when Gravity has access to these things. Sure Rainbow can use Gravity cards too, and their equivalents but eventually it is no real big issue. Procrastination is not unduly bothered by Ice Shield also being able to delay attackers, Arsenic is not afraid of Chrysaora having its own way to stack Poison they simply have their own niche and specific way of doing something that works for them. That something similar exists is no big deal.
Gravity Shield is a good example of how Gravity already shows the beginnings of good synergy with its Otyugh with the ability to munch through small creatures and leave the large ones achieving nothing. If molded right Otyugh will work extremely well with Gravity supplements to Health or ways to cut enemies into bite sized portions and Grav's Otyugh should be more efficient then Rainbow Otyugh as the best Otyugh partners should eventually be other Gravity cards for the new Gravity will be designed to work well with the Gravity that already exists. Gravity can make full use of this while Rainbow won't have sufficient Gravity quantum generation to use so many Gravity cards and will have to make do with alternatives from other Elements which do a satisfactory though second-rate job.
Rainbows leveller though will be the ability to throw out interesting combinations like Otyugh and Firefly Queens and Otyugh with Graveyards for renewable munchings or Quintessence so that the Otyugh doesn't care that Gravity Otyugh grow bigger and stronger faster as it is safe from them and can focus on controlling the other creatures Gravity uses rather then simply racing the Otyugh to gain enough size to swallow them. These tricks and nuances can serve to balance the lower general core effectiveness.
However if we take this route...
The game would be easily balanced by nerfing all these low-cost overpowered cards like Otyugh. With a higher cost, rainbow decks couldn't use them as effectively, but mono-decks could because they can gather that one quantum faster.
Best balance would be achieved by dividing the cards roughly to three categories:
Low cost: Weak creatures with weak abilities (cheap enough for rainbows)
Medium cost: Medium creatures with medium abilities (getting a bit expensive for rainbows)
High cost: Strong creatures with awesome abilities (too expensive for rainbows)
This indeed as I already stated provides a quick fix but what happens later? What happens when Gravity too can give it's Otyugh Health boosts or lower the Health of a crowd of potential Devour Spam food. What is Rainbow left with? The Mono's can now play their strong cards the Rainbows can't match and still have access to a wide range of effects. Sure they don't have the pick and choose of incredibly specific versions of these effects but what does an Otyugh really care if you give it +3 from Plate Armour or from Blessing with the bonus of attack or +1 plus Shield ignorance from Momentum? They're all simply different routes to the same goal. Rainbow will always have more paths but they will eventually all gain at least one route to reach the same destinations and Mono's strength will win out in the end.
Then Rainbow is left in a sorry state poor and hard to play. And there will need to be something done to adress the strength of Mono. If this situation is met with cries of "Nerf Mono!" then sadly the lesson will not be learned and the motions will be gone through again.
This is the most logical solution to this whole "rainbows are overpowered" discussion.
I would disagree. I don't think it's the most logical. Merely the quickest. But that speed could come at a cost. Mono will catch up to Rainbow as the game grows. If we slow Rainbow down now Mono will move too far past it eventually rather then reaching the same finish.
