I am completely stuck in Samorost 3 after finishing the second planet. I got the key, and according to the a video playthrough I need to use it inside the comet.
See here
https://youtu.be/svMgDajMxTI?t=233, to see the trumpet used to open the anthill type hole.
And here
https://youtu.be/ByeZWnT3U8o?t=1338, to see the guy enter with the key, and use it.
But when I use the trumpet on the hole, nothing happens. I am not sure if the trumpet has any sort of mechanics. Do you have to charge it with a particular song first?