Your deck can only comprise cards of two different ink colours (Amber, Amethyst, Emerald, Steel, Ruby, Sapphire)
That's just so good for so many brews and note a few things here
Strong leaders sit in colors with deep support
Now, technically, not using the "choose one" text makes the card play different in certain scenarios (for example, a Naturalize can be redirected from an artifact to enchantment where a modal card cannot change modes when redirected), but for most practical uses they are almost identical
A PSA 8 on a $200+ card still holds value, but the premium over raw is modest (10-20%) PSA 9 (Mint): Nearly perfect with one minor flaw perhaps slightly off-center or a single corner with minimal whitening
With 100 serialized versions of each card, they're incredibly rare and incredibly cool