Hi @Free_Radical,
That’s a great observation, and you’re absolutely right that my advice seems to contradict the general recommendation from the game. Thanks for asking about it!
The strategy I use is a multi-stage approach for highly-developed cities, focusing on frequency, city size, and maxing out potential.
During the main growth phase of a city, frequency is key. The key difference is the time it takes for each box to produce a prize (note that these times are halved when you have the treasure box speedup benefit):
- Brown Box: 15-30 minutes
- Blue Box: 2 hours
- Yellow Box: 4 hours
- Purple Box: 8 hours
In the 8 hours you’d wait for one prize from a purple box, you could have collected from the brown box 16 to 32 times. This is where the “quantity” strategy comes from. The only exception is if another color box shows a ‘flaming lightning,’ which guarantees gems - I would always pick that. I wouldn’t do the same for a ‘bubbling lightning’ (guaranteed passes), as passes are common enough from the brown boxes alone.
The reward size is powered by your city’s size (your total investment in buildings). Each treasure box reaches its maximum payout potential at a different city size, and the brown box requires the largest investment to max out (roughly 1.8 million gems), making it a long-term focus.
However, there is a final stage to this. Once your city is so large that all the treasure boxes have hit their maximum potential, they all pay out the same minimum and maximum reward. At that ultimate end-game point, the time difference no longer matters, and you can pick any box you like.
So, my advice is for that long journey of maxing out your city. It’s a great example of how player-tested strategies evolve as you progress through the game.