I thought that banestrike could only proc every 45 sec*. So how is it I'm watching some lvl 50 shaman proc upwards to 7 times a minute?
Well it has a (40%?) chance to cast on most detrimental spells used, and the melee/ranged chance is more likely to fit the timer, but . . . ya, it is really screwball. I wish they would have left it activated.
I imagine that shaman just doesn't have slayer completed for that creature type, so it's attempting to cast and just resetting, causing the cast spam. See if there are any landing/damage messages: _____ hit _____ for _____ points of physical damage by Banestrike _____. _____ is struck by vengeful spirits. They made the following changes with the August 15, 2018 game update to reduce the annoyance associated with invalid banestrike targets, but otherwise it still attempts to cast:
I thought that once you kill the minimum number to get Banestrike, that the next level (example: you get it for killing 1,000, next level 10,000) reduced the proc time.
It starts at 60 seconds, three ranks of that aa bring it down to 45. The aa has nothing to do with how many of any individual type you kill, there are three over-arching slayer achievements that grant the aa points.
It could also be that the new proc version works on a per type basis with regard to the proc. Also, as with all procs it is possible to get more than the PPM in some situations.