Created by Darkheart for Challenge # 002.

has reverse Hexproof (I must say I prefer Camruth's name for the hexproof ability - Veil).

I know what you mean, Veil feels more mystical. I think the reason Hexproof is good is because it's more specific about what it does -- it's proof against bad spells.

I think the reverse hexproof ability is interestnig: I used it on one or two creatures. But I put it on a black one: shouldn't green get an advantage compared to the other colours?

I lessened the reverse hexproof to making them cost more, still a drawback but not as total.

That makes sense. I like the ability (though if it's 1 more, maybe it should apply to all spells, it'll still affect you more than the opponent, as they will normally only want to target it once).

I'm not sure how much to cost discount to give for the mirror creatures -- this is probably about right (they'll often be useless, but good in the right decks). But in terms of the advantages/drawbacks, if red, black and blue get a 2/2 with a typical drawback, and white gets a bonus, green should probably get nothing or a bonus too.

Made it a blanket ability that affects you & your opponents. This way it is part advantage/part disadvantage.