I think it would be a fun idea to introduce a parlay system for the Up Only Gaming. Or a team aspect where you can select anywhere from 2+ fighters to win where the more you pick, the higher the return but at reduced odds of winning.
The odds could be relative to the other Up Only Gaming predictions and when you have underdogs your return ratio could increase too.
Alternatively, there could be a bonus amount of $KARATE given based on how many of the total fights in the entire card you got right.
Example: 9/9 correct picks and get a bonus!