I think 1AP/0SP is a bit too cheap as it basically makes the curse effect meaningless. But Stabbey's suggestion of 3AP/0SP is pretty interesting. 3AP is a big ask but it's generally always available if the need is there, I might actually use that for my game.
Well, if you think about it, there are enemies that curse ground when you hit them, when they hit you, or even when they move. Not only that but bless doesn't remove cursed ground, it just reverts it to normal ground, which is then just cursed again by the next monster in the round robin initiative. Even at one ap and no source it still wouldn't be super useful...
