After beating Master Necky Sr. in Chimp Caverns, you gain acces to Gangplank Galleon, where the final fight with King K. Rool takes place. Out of all the fights with King K. Rool in the SNES Country games, this one is definitely the easiest. He can be kind of hard if you aren't familiar with his attacks, but otherwise he's very predictable. The only tough part then is reacting to K. Rool's crown throws, which are very quick. But once you get the feel for those, K. Rool becomes very easy to beat (the fight is still really fun though).
As for the game's ending, there are only two versions, with very insignificant differences. After beating K. Rool, you get a small cutscene where Cranky congratulates you. Depending on your save file percentage, Cranky will say one of two things. If you have 100% or less on your save file, Cranky tells you that, had he been playing, he would have found everything and tells you that there are still some bonus rooms that you haven't found. If you have 101% on your save file, Cranky congratulates you on finding every bonus room in the game, stating that you're nearly as good as he used to be (you also get a small star next to your save file percentage if you got 101%).
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