RNG in this game

I currently started running this game and I really enjoy it. From playing myself and from watching runs from other people I tried to figure out how RNG works in this game and how it can be manipulated. The most obvious example of RNG manipulation seems to be the walrus boss of level 3 Sea of Ice. By jumping on the ice you can manipulate the RNG to always throw shells which you need to damage and defeat the walrus. But how does RNG manipulation work with the other bosses? Is it even possible? I'd love to hear your thoughts and experiences on this.

Indiana, USA

This is what Atroz suggested to me long ago, and other than that I don't even remember how to do this run in the slightest any longer.

Enter the Seahorse fight from the top and keep holding up, should get 2 fish. Go back into the top left corner and you should get a double fish again, and then go into the corner again and you should get 1fish 1seaurchin

Just remember to time your attacks correctly so you don't stall the Seahorses attacks. It costs quite a bit of time if you do that

Hope that helps some.

Thanks for your answer. Yes, the Seahorse fight works pretty well this way. Is there a way to manipulate the second boss fight against the moray eels? Swimming in the upper left corner doesn't seem to work for me. Also, the first fight against Ursula is not really possible to manipulate, is it?