Why is it always 3 out of 4 people that connect to each other, but a 4th player isn't connected to anybody?

Exactly. Word!

I get this about 80% of all pantheon/skirmish i try to start. There always just ONE that wont connect to anyone.

Probability most likely. There aren't -many- people for whom this takes place, but just enough to screw up every other connection attempt.

Because 25% of the population can't open a port on their router?

Gaussian distribution.

i concur... happens MOST times.

Frogboy says if people are having connection issue it's mostly likely a problem on their end.  Is it possible that 25% of players are having these issues?

There are just too many people out there that can't configure their router/connection corretly, and for some reason there's always one of them in each game :-/

Or maybe this game is really flawed finally.... ?

I'm always wondered why they don't have a port test of some kind BEFORE you join a game.  Click skirmish, and it runs some packet tests.  A message pops up "Your ports [numbers the game is using] are currently blocked.  Please visit <site> to learn how to open them.  Without open ports chances of connecting properly are greatly reduced.  Thanks."

The 4th person doesn't connect so after a while you cancel. However, if you match again, the same person who didn't connect before now connects with no problems.

Yes, it's as Ravyn said. It seems to have something to do with the specific players involved. At random intervals (albeit rarely), I am that dude who can't connect. It's remarkably frustrating, because everything on my end is clear. I'll get into a new game with all the same people but one guy, and connect easily. Strange.

Yeah I had that issue too!

And to be honest: 2v1+ai is the most annyoing thing in this game at the moment.

I would rather get an exp buff off 50% or so and fight 1v2 than with a feeder ai....

The greatest demigod-day for me were 4times  2v1+ai for me in a row.

After that i tried it once more and the guy which was on my side and didnt' connected played against me and I thought something like "fu** you blabla" but hey it got even better.... the game went so slow it reacted not under 3 seconds. It was beautiful to watch my character standing there, doing nothing while i clicked manical away from that rook and UB. And to see rook slam his hammer on my characters head while i wasnt even stunned...

I stoped to play demigod for that day....

Agreed. I would happily take a 50% HP and/or EXP buff over an AI partner.