i tried to find it and all i could find was someone reporting a 100% stacked sanct failed but has not posted any follow ups and wasnt the posts i was looking for. honestly i was hoping that someone like riot could tell us he tried 100% sancts and it may have happened to him. either way i cant find the old thread and am not even sure if i remember that right.

stack limit of 5 is new to me, i didnt know that, however the most i stacked was 3 cards a couple of times and believe its a better chance of success to not stack cards and just click them singles out after i failed several times chances in the 70-90's but also succeeded a lot of 10-20%'s. maybe i am just lucky a lot but i prefer not to stack. after all if it does fail 4 times in a row you wont know if 1 click at 80% would have done it instead but the chance to get 3 out of the 4 working got the same risk and "no guts no glory" as they say.