Card says +100 luk for 5 secs.. it doesnt take 5 seconds to break the emp, it'll decay, if your crit is not 100 you wont crit consistently after 5 seconds, if you wont crit consistently and you being a crit breaker, your dps wont reach its highest. if you're a crit sinx for pvp, you notice your damage go low after the first 5 second burts, same goes when breaking, after that 5 second burst, it's done.