My son is stuck in Goblin Quest - how can I help him?

My son is stuck and I don’t know how to help him. It is not a coding problem just a matter of how get to another level. Are there some instructions what is he expected to do next? There seems to be some pink trees in the way but he neither I know how to get rid of them. Attached is screenshot of where he is. Any help appreciated!!

You have to click on the diamonds near the previous puzzle to cause the trees to fade away.

Here’s a video demonstrating that.

Thanks for bringing this to our attention.

Kind Regards,
~Chris Murphy