Maybe if every kingpin's bonus increased each time you got a new one. Like, for instance, if the first kingpin gave you 100% boost, then the second gave you 110%, then 120%, then 130% and so on and so forth. Even at just that flat value increase per kingpin, Mr. 34 kingpins up there would now have a 9270% increase instead of a 3400% increase, which would make advancing a bit easier.
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