The Hunger Games

I've noted everything mentioned above.

I also really liked the tournament idea, but after thinking about betrayal, I didn't like it somehow... Betrayal is bad in any case, and besides, it contradicts the rules of the portal.

Of course, I'm not in favor of betrayal, but I think there will be many different situations here, for example...
You and someone else agreed to play together (you're not very good friends with him) (for example, your numbers are 1 and 2) against 2 others (numbers 3 and 4), you got a decent hand, and one of them got a great hand and wins (number 3 defeats number 4)... you're left with three - number 3 and 1 and 2 in an alliance... what do you do next? Fight each other or go to war against the third?