The keystone mastery, Thunderlord's Decree, sometimes will not work for an entire game. It is only specific to you, as I have seen teammates and enemies use it in a game where it was not working for me.
I have had this happen to me in 4/5 games, where I played Ekko in 4 of them and Fizz in the 5th. It did not appear to be champion specific, as I was playing Ekko in the game where it was working.
Maybe because it has a 30 second cooldown... so you just weren't noticing it?
http://boards.na.leagueoflegends.com/en/c/bug-report/O1nL4Uus-gameplay-thunderlords-decree-not-always-working I had the same problem. A few of my friends wanted to test and see so we went into a co-op vs AI to see.
Ive also had this problem when it does work you can see the cd on the right side of where your buffs would be and you can see the cd go down and it has a pretty notciable animation which also doesnt go off
Still having this problem, Riot support doesn't believe that it's a bug, but it is -.-
