New promotions like stake vs eddie or lvl up but hold daily. There is a large data already about games(game x potential, how rare is x multi etc.) currently on stake so you could create system that creates daily challenges on totally random games. Multiplier to hit would be calculated based on slots data so games with lower x potential have lower X range. For example around 10-20% of max win so on games like gates it would be 500-1000x and on games like wanted it could roll from 1250 to 2500x.
Challenges like this would bring new players to old games that new players don't know. It would work like promotions mentioned above but with higher variety of providers and games
Stake: matidv4