If the chart I saw is right, 5% of the time Goddess of Wishes gives 35 diamonds. Since Wishing Wells seem to have been discontinued, this is about as good as it gets for free diamonds now. 9% of the time it gives 3 knowledge points. For comparison's sake, a Carting Library is 2 squares and gives 1 KP every 24 hours. So a 4 square Goddess of Wishes giving 3 KP in 12 hours is actually 3x as efficient as a Carting Library. So 14% of the time, you get decent rewards from it.

Unfortunately, the other 86% of the time is either gold, supplies, or goods. And the amounts for all of these are WAY low.

I think a more appropriate comparison of Carting Library to GoW would be this:

Assume maximum production (i.e., always collecting the minute it is available):

Over 30 days, Carting Library will give you 30KP @ 1KP per day, guaranteed, at a cost of 2.5 squares.

Over 30 days, you can collect 60 times from GoW, and if it really is a 9% chance, that works out to (60 * 0.09) * 3KP, or 16.2 KP, at a cost of 5 squares.

So just from a KP standpoint, GoW is

**far **less efficient than a Carting Library -- about half as efficient in terms of raw KP production, and about one quarter as efficient in terms of KP production per square.

Of course, you also have a shot at diamonds, and if your 5% number is correct, then you can expect to see (60 * 0.05) * 35 = 105 diamonds. Personally, I think that's a relatively meager sum. Also important to note, a 5% drop rate on diamonds over 60 hits means you also have a 4.61% chance to

**not receive diamonds at all**, and that 4.61% chance only climbs higher the further away from 'maximum production' you go (i.e., the more pickups you miss because you have a life and can't always be checking Elvenar).

The other rewards (goods, gold, supplies) seem like they come at such low quantities that they're borderline inconsequential to even do math for, but either way I think it's pretty clear that GoW is a rather lackluster reward as the capstone for completion of the entire event. It could be argued, of course, that it's just a small bonus -- that the real reward for the event is the evolving building and daily prizes and such -- and that we should be happy with a bonus building even if it's not super great. I'm not sure I buy that argument, personally, but I understand those that do.