World World Event - Spelunk

This would be a diet version of lootrun's spelunk challenge, which would work with parties.
Treat it as a timed race.

Since this world event would reset all chest cooldowns of caves, maybe it should occur less often.


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The world event grants limited amount of time to complete as many caves as possible for all party members.
At the beginning of world event, an empty treasure chest spawns, and players scatter to clear caves.

In addition to standard loot, opening Cave chests will grant 1-3 treasure coins (depending on chest tier).
When all chests were opened in a cave, additional 2-8 treasure coins are granted (depending on dungeon's length).

These treasure coins must be deposited into the empty chest at world event's spot.
The more treasure coins party members collect, the greater the rewards will be at the end of the event.



The world event could last around 3 minutes, and the chest cooldown could be up to 1 minute.
Not sure of the math formula to use for end rewards so that it suits both solo and any party size.