I suck at handling Krark triggers guys, but I'm good at coding. Which means...
I'm actually really good at handling Krark triggers.
You can change any number on the app by tapping on it (+1) or long-pressing (reset to 0).
Feel free to mess around with the app, as there's nothing that can go so wrong that's not fixable by forcing it to close and reopen.
Keep in mind that when looping spells like Bonus Round, or spells that create copies of certain engine pieces, there's the risk of going exponential with the amount of computation the app will start doing. There is a limit of 100 automatic actions the app takes before stopping a loop but that can still get nasty if you manually keep looping until a certain threshold. Again, in that case you just force the app to close, and reset the gamestate with the top-right button.
You can mess with theme customization, you can save any number of spells for later re-use and load them before editing them further if your actual gamestate is really crazy, just experiment.
There is an "Info" section in the menu as well, with a list of all the relevant engine pieces that the Krarkulator can simulate, so you can see the actual images of the cards to understand how they work and what the various buttons of the app refer to.
P.S.: The badass quote from the intro is ripped from one of the best human beings on this planet, Mark Rober (https://www.youtube.com/watch?v=MHTizZ_XcUM)