Multistrike Changes

While discussing mechanic changes ealier today, it was pointed out to me that I hadn't actually read the latest patch notes regarding the changes to multistrike.   I guess I just assumed they were the same as before, so I skipped that section and went right to the good stuff.

Anyhow,  this is from the Dev Watercooler:

New Stat: Multistrike 
A new stat in Warlords of Draenor, Multistrike grants your spells, abilities, and auto-attacks additional chances to activate. If you’ve been following along since BlizzCon, you may remember that in our early plans, your Multistrike chance would split between two rolls and effectively have a 200% cap. We’ve since changed that to make it more clear and intuitive: the full chance is given to both rolls, with a 100% cap.
Now Multistrike grants your spells, abilities, and auto-attacks the chance to activate up to two extra times at 30% of normal effectiveness. For example, if you have 55% Multistrike and cast a Fireball that does 1000–1100 damage, you’ll have two separate 55% chances to automatically follow with another smaller Fireball that does 300–330 damage. That means every time you cast Fireball, you have a chance to see one big-damage Fireball, and then two smaller-damage Fireballs leave your hands in quick succession.
A couple things are a little unclear there.   Let's use their example; with 55% multistrike, and you cast an arcane shot (fireballs are for support classes) that does 1000 - 1090 damage.   You have 2, independent, 55% chances to automatically follow with another, third-the-damage arcane shot.   However,  you have a 79.75% chance of getting at least one third-the-damage arcane shot (which is the same as to say, you have a 20.25% chance of not seeing any), and you have a 30.25% chance of seeing 2 third-the-damage arcane shots.   

For those who don't remember basic probabilities from high school, for independent probabilities we add them together as such:

P(x) = 1 - (Chance to Fail / Total Chances) * (Second Chance to Fail / Second Total Chances)

Or, for our case, where the odds for the first and second will always be the same, simply:

P(x) = 1 - ((Chance to Fail / Total Chances) ^2)

Our chance, then, to get at least 1 multistrike will always be:

P(x) = 1 - (1- MS%) ^2

So if we have 25% Multistrike, we'll have a 43.75% chance of getting at least 1 third-the-damage shot. If we have 30% Multistrike, we'll have a 51% chance of getting at least 1 third-the-damage shot. The numbers on up to 55% look like:

Multistrike Chance to get 1
5% 9.75%
10% 19.00%
15% 27.75%
20% 36.00%
25% 43.75%
30% 51.00%
35% 57.75%
40% 64.00%
45% 69.75%
50% 75.00%
55% 79.75%

This is particularly interesting because the chance to get at least 1 is going to change dramatically as the expansion goes on.  Notice how going from 5% to 10% MS gives you a 9.25% increased chance to get at least 1 Multistrike,  but going from 50% to 55% MS is only a 4.75% increased chance to get at least 1 Multistrike.   This is very important for SV hunters, because, at least as it's been explained so far,  getting at least one multistrike on each Black Arrow tick is going to keep you swimming in free Explosive Shots, since you'll be able to use one free ES with each tick, and use the reset Explosive Shot CD between each of those. 

At higher Multistrike ratings, we'll need to start worrying about capping our Explosive Shots, because the chance to get both Multistrikes grows in an inverted way to how the chance to get at least one grows:

Multistrike  Chance to get both
20% 4.00%
25% 6.25%
30% 9.00%
35% 12.25%
40% 16.00%
45% 20.25%
50% 25.00%
55% 30.25%
60% 36.00%
65% 42.25%
70% 49.00%
75% 56.25%
80% 64.00%
85% 72.25%
90% 81.00%
95% 90.25%
100% 100.00%

Hopefully we'll have a new alpha build with the LnL changes included soon, so we can start to get a better feel for how the devs are thinking it will work.   As it is, once we get up around 50% multistrike, we'll be doing more Explosive Shots than we even are now, so I imagine something will be changed.   Hopefully this will be a fun mechanic, though.   


  1. So if I read this right, SV seems like it will be a bit gear dependent at first, if Multistrike ends up one of the top 2 stats for the spec. I'm also getting the impression that stacking more Multistrike could make SV damage less bursty, eventually.

    1. One person I was talking to about it was wondering if we would have to use all of our LnL procs immediately, or if we might save them up for a trinket proc, giving us a small measure of on demand burst.

      It'll definitely be interesting to see how it all works out. So far I'm picturing something like boomkin's starsurge, but with charges instead of having only one.