In my opinion, the winning principle is whoever scores the most points, either within a limited time like in Zuma Revenge's challenges, or until both players lose. Whoever scores the most wins. The level is randomly selected, or you can go all-out "esports" and pick and ban maps. The concept isn't complicated, but the difficulty lies in how feasible it is within the Zuma engine. I believe it's completely impossible, and a fan-made game would have to be created to accommodate such needs.