The True Ending of Kirby and the Forgotten Land can be unlocked after completing all the Forgo Dream: Isolated Isles stages in the game. This How to Unlock the True Ending guide will tell you what this involves.
To begin with you need to complete Lab Disovera, the final stage of the main story. This includes defeating the three bosses and seeing the credits scene. After this you need to return to Waddle Dee Village where you will discover that the Beast Pack now reside there. Climb the Observation Tower to the left of the village square using the ladder that is next to the Waddle Dee stage and talk to the (former) Beast Pack boss. If you now look at the strange crack in the sky you will be taken to the Forgo Dream: Isolated Isles which is a world that consists of 7 levels with a new post-game collectible that can only be found in this area.
In order to unlock the final boss you need to complete 6 levels which are all basically remixed versions of the worlds you explored previously into one. You will have to deal with new threats, new puzzling challenges, and totally new attacks from the boss fights. Your objective is to save Leongar by collecting 250 Soul Shards. You will find around 50 Soul Shards in each level which means you need to collect almost all of them on each level to unlock the final level.
Take a look at our Beginner Tips and Tricks to get help in Kirby and the Forgotten Land.
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