dude dave rebirb upgrade is impossible it took me nearly a hour to get mua'd bird and THE NEXT ONE COSTS 7.5B??? bro u expect me to grind for 500 years? just to get one upgrade it took me nearly a hour or more to get the mua'd bird
fastest way to get golden popcorn is to equip a fish that gives +% to golden popcorn (in Expedition tab, only fishable in expedition worlds) and a fash that increases collection range then let it run over night. upgrade golden popcorn value to ~50 before buying any upgrades that do anything other than get you more golden popcorn
it still takes a long time but now if i let it run overnight i get billions