Tony, A player can sanction you two times in a row a day: once if you have enough health and second after he heals you - which can be done only once per day.
Regarding players that sanction you without you attacking them first: you can be sanctioned from several places, one of them being your profile. There may be some that go to your profile and sanction you from there, for example.
As I've said, we're considering adding a few more rules to try and eliminate sanctioning a player too often, although we don't want to force too many of them on the game. Hope this helps, thanks.
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