I noticed a bug with thunderlords decree... It works when a single champion has it... but if multiple champions on the same team have it... then because each champion attacks a different champion... the attack counter resets... making you unable to procc it... I dont have any definitive evidence but it works if I fire it in rapid succession before any of my teammates that have it attack other champions
I have noticed the same thing where I have been unable to proc it when people on my team have the mastery as well. I am assuming that this is what is happening. its extremely frustrating to have gone 18 points down to pick it up and not get to use it.
This actually explains why I wasn't able to proc it the other day when I was playing Lux support. Our Ez mid had it I believe. I kept trying to burst the enemy ADC with a quick Q+AA+E+AA and even with 4 consecutive hits, I couldn't get it to proc.
