The particularly nasty Wordstone placed in Jon's possession was the Painted Wordstone.
The bearer of this stone would be transformed to suit the first three adjectives they utter each day while holding the stone, the very second they speak the third.
Every day, the victim is free to be cursed and cursed again.
These changes are not wishes in themselves and so may be countered. However the stone itself will resist any attempt to remove these attributes - though, as bound by Fae law, a perfectly worded wish can remove these alterations completely.
It should be noted that while these changes are not permanent wishes most certainly are, and so with each day the victim is cursed, the more difficult it will be to find a solution in wishes which does not contradict a previous wish...