This older (maybe father or grandfather) tree than Whispy Woods comes to challenge Kirby sort of near the end of Kirby Star Allies. I liked this one mainly because I never expected to see this tree boss ever.
And he's essientially a more difficult to defeat Whispy Woods. They have similar tricks, so at least that makes it easier.
But in due time he will timber down to defeat. I don't think many players would actually lose to them unless they had really poor skill.