You might expect a more simple, casual game like Pikmin 4 to have a straightforward path to a single ending. While that was the case for prior games, this time around you will need to do quite a bit more work if you want to see the true conclusion to this tale. If you only play to the point of seeing the credits, you are leaving nearly half the game on the table unplayed. The post-game content is arguably longer than the main game and is the only way to see the true ending. Here's how you can see Pikmin 4 top its true conclusion.
Note that we will only spoil the names of locations and bosses below, not the content of either ending.
How to get the true ending
The normal path to credits will take you through several stages and bosses, and even roll credits, but isn't where your journey really ends.
Step 1: Go through the main missions through Hero's Hideaway.
Step 2: Beat the Leafy Showdown and watch the ending credits.
Step 3: If you don't have it already, you will now need to collect 11,000 Sparklium to unlock the new Giant's Hearth stage.
Step 4: Your new mission is titled "Cure Oatchi" and leads you to the Cavern for a King in the Primordial Thicket.
Step 5: Make your way through this boss rush until you reach the very bottom.
Step 6: Defeat the true final boss of the game, Louie and the Ancient Sirehound.
Step 7: Defeating this boss will reward you with the Gift of Friendship that you can use to cure Oatchi.
Step 8: Enjoy the true final cutscene of the game.