Whenever, I'm searching for new caves, I get the usual stuff... a few potions here and there. That is, UNTIL I get down to my last 2-4 bread. At this point there seems to be a MUCH greater chance of big, juicy caves with multiple defenders, like fight 3 battles for 20-25 potions.
Which of course I cannot do, because I have less than 6 bread. So I search again, and often I'll get another big, juicy cave.
I almost never get these mega-caves when my bread is up higher. But gee, if I only spent 50 gems, I'd have enough to fight them. I'm 90% certain the cave search algorithm is being manipulated to try to get players to buy bread with gems. What do you think?