If we're gonna be able to join them like 4-5 times a day and have to do incredibly well just to get our money back, then it should be free. It's very hard to make money on this site, and paying 15T per game is waaaaaaaaaaay too much.
No, not free. That would make it easy for people to get tons on Karma. All you would need is a 13 person "premade" with a rotation and everyone would get 100+ Karma a DAY!