Instead of a single explosion, release a chain of 3 consecutive explosions, each dealing 520% weapon damage as Fire.
Conversely, the in-game tooltip of EB-CR says: “Gather a mass of energy around you that explodes after 1.5 seconds, dealing a chain of 3 explosions around you for 520% damage as Fire.”
So this would be 3x3 = 9 Explosions, because the initial explosion is replaced. Unless they changed the functionality somewhere and the rune no longer replaces the initial explosion and the website was just never updated.
Frankly, I find this unlikely. It was probably 9, and always has been, 9 explosions when paired with Wand of Woh.
If I recall correctly, I think I came to the conclusion it was more then 9. I watched it and seen it wasn’t what I thought it was, but it also wasn’t what another person thought it to be either.
You’re looking at the wrong thing. Chain Reaction isn’t the thing that’s 4 in 3*4, Wand of Woh is the thing that’s 4.
Wand of Woh gives 3 additional explosions, not 3 total explosions. That’s the way it’s worded. This is very easy to see with runes other than Chain Reaction, e.g. try it with Flash. It’s easy to count 4 explosions. So Wand of Woh gives 4x explosions. It has always been this way, as far back as 2.0.6 it was worded as “3 additional explosions”, so 4 total.
Now consider with Chain Reaction. Wand of Woh gives 4x explosions, so Chain Reaction * Wand of Woh = 3 explosions times 4 = 12 explosions.
I don’t know why you have it in your head that it was 9 (maybe someone tried to count them in real time in the past and for some reason came up with 9 because they missed a few of the quick ones in the middle), but it’s definitely 12 now. And I’m 99% sure it always has been.
I slowed it down and counted them, there’s definitely 12. They group up a bit in the middle so it’s easy to miss a few that come out in rapid batches of 2 or 3 in the middle.