Or rather the Gold Black Hole. Assuming the Treasure Hoard starts out at level 1, donations required to get it to max level look like this:
Best case, donating only mythic treasures in chunks of 5:
1001 mythic treasures and 133,422,400 gold required.
Donating only mythic treasures in chunks of 1:
1001 mythic treasures and 133,832,000 gold required.
Donating only common treasures in chunks of 5:
50050 common treasures and 6,696,200,000 gold required.
Worst case, donating only common treasures in chunks of 1:
50050 common treasures and 6,696,640,000 gold required.
Donating treasures one by one or in chunks of 5 makes next to no difference for the total cost, so there’s no reason at all to hold back. There’s a new Faction each month, requiring the same amount of donations to max out, so completionists should better get started farming right away.
I can’t help but wonder at the scope of the task at hand. Is this really intentionally so way past impossible to achieve? Or is there a design bug in the cost formula? Meaning we should hold back on improving the Treasure Hoard because costs will get lowered significantly once the devs realize 6 billion gold might be a bit much to ask for?