I'd say strange hats but think they don't work anymore XD
Basically their using their invis just like before, if you're not stunned and they go invis for their cds throw somethinglike tkpull or nontarget aoes at where you last saw them
Don't move in trops, rather try to cc them as long as those are up and yeah, seems like they aren't this strong vs a summoner, just gotta survive till they go invis for their cds, managed to hit dark pact and heal to full during those phases more than once already XD
grouppvp and them beeing weak? they go upfront burst someone down or lock a healer then poof and runs behind their lines + they make perfect target callers for any kind of melee dps in pvp due to the tons of kds.