Hearthpwn

Hey guys, I am keeping myself busy evaluating Power of Creation and hit a math problem that I don't know how to solve.

Assume we want to find odds to hit  X number of outs out of Y cards in discover pool. If all options are neutral cards, formula for that is quite simple 1-((Y-X)/Y*(Y-X-1)/(Y-1)*(Y-X-2)/(Y-2). For example if we need two outs from a 10-card pool, it is is 1-(8/10*7/9*6/8)=0.5333

But there are a problem when we add class cards. One can say that they have x4 higher chance to appear, so you can simply count them for 4 card. But this is incorrect. If we'll do that, we'll assume that it is possible to hit the same class card twice, which is not true. For example: in the most basic case of 3 cards(1 of them is a class card) and 1 neutral out, we'd get a formula like 1-(4/5*3/4*2/3) giving us 0.6 instead of the correct result of 1.

Are there any elegant mathematical way to solve this problem? Or is the brute force simulation is the only practical way to do it?

Unfortunately there isn't a way to do it other than how you treated every class card as 4, and then manually make the considerations to decrease the total number of cards by 4 at the right times. Meaning we have to go through the 8 possible comboes of class and neutral cards.
If X is number cards we want to hit, Y is total cards with weight (class cards are 4x), Z is number of class cards we don't want to hit and W is number of neutral cards we don't want to hit, (X+4Z+W=Y)
then we consider a comboes of class-neutral cards in a failed discover as such:
N-neutral, C-Class
NNN: 1-(W/Y*(W-1)/(Y-1)*(W-2)/(Y-2))
NNC: 1-(W/Y*(W-1)/(Y-1)*4Z/(Y-2))
NCN: 1-(W/Y*4Z/(Y-1)*(W-1)/(Y-5))
NCC: 1-(W/Y*4Z/(Y-1)*(4Z-1)/(Y-5))
CNN: 1-(4Z/Y*W/(Y-4)*(W-1)/(Y-5))
CNC: 1-(4Z/Y*W/(Y-4)*(4Z-1)/(Y-5))
CCN: 1-(4Z/Y*(4Z-1)/(Y-4)*W/(Y-8))
CCC: 1-(4Z/Y*(4Z-1)/(Y-4)*(4Z-2)/(Y-8))

Simplifying what you can you get: 8-(a+b+c+d)/Y
with:
b=W*4Z*(W+4Z-2)/(Y-1)*(Y-5), c =b*(Y-1)/(Y-4), a=b*(W-1)*(Y-5)/4Z(Y-2), d=c*(4Z-1)*(Y-5)/W(Y-8)
or just the sum of the 8 ezpressions above. That's the best answer.

Wasn't weighted odds for class cards removed from the discover mechanic some time ago?

This thread was made in March 2019, when that was true. 

I didn't even notice. Thanks, i thought my memory was failing me!