The idea is, that if you playing a pillar/towerless deck, or a deck with a low number of them you can play this Curse to deal damage on your turns passiv. It seems to me the best color could be earth for that. Cause you have the option to destroy pillars/towers or to punish for need of many pillars/towers.
Cursed Stones -- Permanent -- Costst???
Both players get 1 damage every turn for every pillar they control, diveded by 2.
Any suggestions?