Okay, so I got up to the 4th stage in this water exploration.

5th stage, I can make no dent at all. Impossible for me.

So 4th, look, I still get 1-2 of these rocks per run. Sometimes I get 30 pokestones, which is like a refund for buying a ticket with stones, but it's uncommon.

As for the rewards themselves.

two 18 qual monsters are here. It's very hard to build a team around them. But obviously they work with eachother. They're also, and this is exciting, both materials for a 20 qual monster. After which you have to make/hope for one more 18 from some event in the future. And have the october log in girl (wtf?). So in the beta servers some whale will probably have a 20 qual soon.

30 event rocks per summon. So you can assume 300 rocks per monster if the chances did not grow. I think 250is a reasonable estimate if you dump all your stones at once. 10%+10.5%+......13%. Basically you need slightly over 8 summons to hit 100% cumulative. There's a better equation for this but I don't remember it so w/e.

But with how chances work that means there will be some of us unable to pull the monster even with 600 of these rocks

so using me as an example for my own self,

250 /1.5 *30 = 5000 pokestones if you were to try to buy one of these straight, as an average.

Some lucky bastard will pull them both within 100 rocks.

And we're assuming these percentages are honest, a growingly difficult thing to assume in modern times.