SFII CE: Verifying number of possible matches

It was 1992 when the Street Fighter II Champion Edition (CE) came out. The ad in gaming magazine says "It is Boss vs Boss". Wow, now you can see who really can use Guile. (But Guile's power has toned down ever since). Now you can use that M.Bison flaming pyscho crusher! There are other things that forces the game to change... how does Vega do that climbing move when you don't have a cage on every stage?

Look, there is a number on the game cabinet. "78 possible matches".

How do you get that 78? You have 12 characters to choose from, and you use 2 at a time.... and order does not matter (Ryu vs Ken is same as Ken vs Ryu).

That sounds like the need for Combination, with n=12, k=2.

Well I am playing with Ryu, I am not going to bother calculating this.... and 20+ years went by. Ok, it isn't hard to carry this out even without a calculator. The big (n-k)!=10! just cancels out. So you have: 12×11/2 = 66. It is not 78.

Oh did the Capcom guys have it wrong? or did I have it wrong? Look this is a real-life math situation. If you are to draw that cabinet art and your boss ask you to put the number of possible matches you need to do such calculation.

Ah look at the ultimate feature on the lower right: Ken vs Ken! 66 + 12 mirror matches = 78 possible matches! It feels great to solve a problem (like verifying an answer for an odd number question from the back of text book)

Now, can you figure out the number of possible matches for Super? (16 total). Oh in Super-Turbo there is this Akuma! I may wait another 20 years to carry out such calculation. So I am going to use the textbook trick: leave-to-reader.